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pubmed23n0001_0
[Biochemical studies on camomile components/III. In vitro studies about the antipeptic activity of (--)-alpha-bisabolol (author's transl)].
(--)-alpha-Bisabolol has a primary antipeptic action depending on dosage, which is not caused by an alteration of the pH-value. The proteolytic activity of pepsin is reduced by 50 percent through addition of bisabolol in the ratio of 1/0.5. The antipeptic action of bisabolol only occurs in case of direct contact. In ca...
[Biochemical studies on camomile components/III. In vitro studies about the antipeptic activity of (--)-alpha-bisabolol (author's transl)]. (--)-alpha-Bisabolol has a primary antipeptic action depending on dosage, which is not caused by an alteration of the pH-value. The proteolytic activity of pepsin is reduced by 50 ...
21
pubmed23n0001_1
[Demonstration of tumor inhibiting properties of a strongly immunostimulating low-molecular weight substance. Comparative studies with ifosfamide on the immuno-labile DS carcinosarcoma. Stimulation of the autoimmune activity for approx. 20 days by BA 1, a N-(2-cyanoethylene)-urea. Novel prophylactic possibilities].
A report is given on the recent discovery of outstanding immunological properties in BA 1 [N-(2-cyanoethylene)-urea] having a (low) molecular mass M = 111.104. Experiments in 214 DS carcinosarcoma bearing Wistar rats have shown that BA 1, at a dosage of only about 12 percent LD50 (150 mg kg) and negligible lethality (1...
[Demonstration of tumor inhibiting properties of a strongly immunostimulating low-molecular weight substance. Comparative studies with ifosfamide on the immuno-labile DS carcinosarcoma. Stimulation of the autoimmune activity for approx. 20 days by BA 1, a N-(2-cyanoethylene)-urea. Novel prophylactic possibilities]. A r...
22
pubmed23n0001_2
Effect of etafenone on total and regional myocardial blood flow.
The distribution of blood flow to the subendocardial, medium and subepicardial layers of the left ventricular free wall was studied in anaesthetized dogs under normoxic (A), hypoxic (B) conditions and under pharmacologically induced (etafenone) coronary vasodilation (C). Regional myocardial blood flow was determined by...
Effect of etafenone on total and regional myocardial blood flow. The distribution of blood flow to the subendocardial, medium and subepicardial layers of the left ventricular free wall was studied in anaesthetized dogs under normoxic (A), hypoxic (B) conditions and under pharmacologically induced (etafenone) coronary v...
23
pubmed23n0001_3
Influence of a new virostatic compound on the induction of enzymes in rat liver.
The virostatic compound N,N-diethyl-4-[2-(2-oxo-3-tetradecyl-1-imidazolidinyl)-ethyl]-1-piperazinecarboxamide-hydrochloride (5531) was analyzed as to its effect on the induction of tryptophan-pyrrolase and tyrosineaminotransferase in rat liver. 1. The basic activity of the enzymes was not influenced by the substance ei...
Influence of a new virostatic compound on the induction of enzymes in rat liver. The virostatic compound N,N-diethyl-4-[2-(2-oxo-3-tetradecyl-1-imidazolidinyl)-ethyl]-1-piperazinecarboxamide-hydrochloride (5531) was analyzed as to its effect on the induction of tryptophan-pyrrolase and tyrosineaminotransferase in rat l...
24
pubmed23n0001_4
Pharmacological properties of new neuroleptic compounds.
RMI 61 140, RMI 61 144 and RMI 61 280 are newly synthetized N-[8-R-dibenzo(b,f)oxepin-10-yl]-N'-methyl-piperazine-maleates which show interesting psychopharmacologic effects. This work contains the results of a study performed with these three compounds, in order to demonstrate their neuropsycholeptic activity in compa...
Pharmacological properties of new neuroleptic compounds. RMI 61 140, RMI 61 144 and RMI 61 280 are newly synthetized N-[8-R-dibenzo(b,f)oxepin-10-yl]-N'-methyl-piperazine-maleates which show interesting psychopharmacologic effects. This work contains the results of a study performed with these three compounds, in order...
25
pubmed23n0001_5
[Studies on the action of an anticholinergic agent in combination with a tranquilizer on gastric juice secretion in man].
A double-blind study with intra-individual comparisons was carried out to investigate the effects of 15 mg of (8r)-3alpha-hydroxy-8-isopropyl-1alphaH-tropanium bromide(+/-)-tropate (Sch 1000), 15 mg Sch 1000 + 10 mg oxazepam, 10 mg oxazepam and placebo with oral administration in randomized sequence on gastric juice vo...
[Studies on the action of an anticholinergic agent in combination with a tranquilizer on gastric juice secretion in man]. A double-blind study with intra-individual comparisons was carried out to investigate the effects of 15 mg of (8r)-3alpha-hydroxy-8-isopropyl-1alphaH-tropanium bromide(+/-)-tropate (Sch 1000), 15 mg...
26
pubmed23n0001_6
Lysosomal hydrolases of the epidermis. I. Glycosidases.
Seven distinct glycosidases (EC 3.2) have been characterized in guinea-pig epidermis. Their properties indicate them to be of lysosomal origin. The 'profile' of the epidermal glycosidases is significantly different from that reported for whole skin, the activities of beta-galactosidase and beta-acetylglucosaminidase be...
Lysosomal hydrolases of the epidermis. I. Glycosidases. Seven distinct glycosidases (EC 3.2) have been characterized in guinea-pig epidermis. Their properties indicate them to be of lysosomal origin. The 'profile' of the epidermal glycosidases is significantly different from that reported for whole skin, the activities...
30
pubmed23n0001_7
Lysosomal hydrolases of the epidermis. 2. Ester hydrolases.
Five distinct ester hydrolases (EC 3-1) have been characterized in guinea-pig epidermis. These are carboxylic esterase, acid phosphatase, pyrophosphatase, and arylsulphatase A and B. Their properties are consistent with those of lysosomal enzymes.
Lysosomal hydrolases of the epidermis. 2. Ester hydrolases. Five distinct ester hydrolases (EC 3-1) have been characterized in guinea-pig epidermis. These are carboxylic esterase, acid phosphatase, pyrophosphatase, and arylsulphatase A and B. Their properties are consistent with those of lysosomal enzymes.
31
pubmed23n0001_8
A serum haemagglutinating property dependent upon polycarboxyl groups.
A serum agglutinin reactive with red cells in the presence of polycarboxyl groups is reported. It is likely that this represents an additional example of the type of agglutinin previously described as agglutinating red cells in the absence of ionized calcium. Experimental evidence is presented indicating that it is fre...
A serum haemagglutinating property dependent upon polycarboxyl groups. A serum agglutinin reactive with red cells in the presence of polycarboxyl groups is reported. It is likely that this represents an additional example of the type of agglutinin previously described as agglutinating red cells in the absence of ionize...
32
pubmed23n0001_9
Effect of human erythrocyte stromata on complement activation.
Stroma from either normal or PNH-like red cells is capable of inhibiting, to some extent, lysis in the sucrose test and enhancing lysis in the acidified-serum test. The same opposing effects are displayed by the exclusion peaks from Sephadex G-200 obtained from each stroma preparation, suggesting that the same factor c...
Effect of human erythrocyte stromata on complement activation. Stroma from either normal or PNH-like red cells is capable of inhibiting, to some extent, lysis in the sucrose test and enhancing lysis in the acidified-serum test. The same opposing effects are displayed by the exclusion peaks from Sephadex G-200 obtained ...
33
pubmed23n0001_10
The effect of o-salicylate upon pentose phosphate pathway activity in normal and G6PD-deficient red cells.
The effect of the major metabolite of aspirin, namely salicylic acid, upon the pentose phosphate pathway (PPP) of normal and G6PD-deficient red cells has been studied. Salicylic acid was shown to inhibit this pathway in proportion to the amount present. At any concentration of this substance there was greater inhibitio...
The effect of o-salicylate upon pentose phosphate pathway activity in normal and G6PD-deficient red cells. The effect of the major metabolite of aspirin, namely salicylic acid, upon the pentose phosphate pathway (PPP) of normal and G6PD-deficient red cells has been studied. Salicylic acid was shown to inhibit this path...
35
pubmed23n0001_11
The effects of processing of barley-based supplements on rumen pH, rate of digestion of voluntary intake of dried grass in sheep.
1. In one experiment the effect on rumen pH of feeding with restricted amounts of whole or pelleted barley was studied. With whole barley there was little variation in rumen pH associated with feeding time, but with pelleted barley the pH decreased from about 7-0 before feeding to about 5-3, 2--3 h after feeding. 2. Th...
The effects of processing of barley-based supplements on rumen pH, rate of digestion of voluntary intake of dried grass in sheep. 1. In one experiment the effect on rumen pH of feeding with restricted amounts of whole or pelleted barley was studied. With whole barley there was little variation in rumen pH associated wi...
36
pubmed23n0001_12
Poly(8-aminoguanylic acid): formation of ordered self-structures and interaction with poly(cytidylic acid).
Poly(8-aminoguanylic acid) has in neutral solution a novel ordered structure of high stability. The 8-amino group permits formation of three hydrogen bonds between two residues along the "top", or long axis, of the purines. The usual hydrogen bonding protons and Watson-Crick pairing sites are not involved in the associ...
Poly(8-aminoguanylic acid): formation of ordered self-structures and interaction with poly(cytidylic acid). Poly(8-aminoguanylic acid) has in neutral solution a novel ordered structure of high stability. The 8-amino group permits formation of three hydrogen bonds between two residues along the "top", or long axis, of t...
37
pubmed23n0001_13
Effect of pH on substrate and inhibitor kinetic constants of human liver alanine aminopeptidase. Evidence for two ionizable active center groups.
The presence of at least two ionizable active center groups has been detected by a study of the effect of pH upon catalysis of hydrolysis of L-alanyl-beta-naphthylamide by human liver alanine aminopeptidase and upon the inhibition of hydrolysis by inhibitors and substrate analogs. Octanoic acid, octylamine, and peptide...
Effect of pH on substrate and inhibitor kinetic constants of human liver alanine aminopeptidase. Evidence for two ionizable active center groups. The presence of at least two ionizable active center groups has been detected by a study of the effect of pH upon catalysis of hydrolysis of L-alanyl-beta-naphthylamide by hu...
38
pubmed23n0001_14
Formation of transient complexes in the glutamate dehydrogenase catalyzed reaction.
The reaction of glutamate dehydrogenase and glutamate (gl) with NAD+ and NADP+ has been studied with stopped-flow techniques. The enzyme was in all experiments present in excess of the coenzyme. The results indicate that the ternary complex (E-NAD(P)H-kg) is present as an intermediate in the formation of the stable com...
Formation of transient complexes in the glutamate dehydrogenase catalyzed reaction. The reaction of glutamate dehydrogenase and glutamate (gl) with NAD+ and NADP+ has been studied with stopped-flow techniques. The enzyme was in all experiments present in excess of the coenzyme. The results indicate that the ternary com...
39
pubmed23n0001_15
Human brain and placental choline acetyltransferase: purification and properties.
Choline acetyltransferase (EC 2.3.1.6) catalyzes the biosynthesis of acetylcholine according to the following chemical equation: acetyl-CoA + choline in equilibrium to acetylcholine + CoA. In addition to nervous tissue, primate placenta is the only other animal source which contains appreciable acetylcholine and its bi...
Human brain and placental choline acetyltransferase: purification and properties. Choline acetyltransferase (EC 2.3.1.6) catalyzes the biosynthesis of acetylcholine according to the following chemical equation: acetyl-CoA + choline in equilibrium to acetylcholine + CoA. In addition to nervous tissue, primate placenta i...
40
pubmed23n0001_16
Stabilization of the globular structure of ferricytochrome c by chloride in acidic solvents.
Increasing concentrations of chloride were found to increase the resolution between two visible absorbance spectral transitions associated with acidification of ferricytochrome c. Analysis of a variety of spectral and viscosity measurements indicates that protonation of a single group having an apparent pK of 2.1 +/- 0...
Stabilization of the globular structure of ferricytochrome c by chloride in acidic solvents. Increasing concentrations of chloride were found to increase the resolution between two visible absorbance spectral transitions associated with acidification of ferricytochrome c. Analysis of a variety of spectral and viscosity...
41
pubmed23n0001_17
A competitive labeling method for the determination of the chemical properties of solitary functional groups in proteins.
The properties of the functional groups in a protein can be used as built-in-probes of the structure of the protein. We have developed a general procedure whereby the ionization constant and chemical reactivity of solitary functional groups in proteins may be determined. The method may be applied to the side chain of h...
A competitive labeling method for the determination of the chemical properties of solitary functional groups in proteins. The properties of the functional groups in a protein can be used as built-in-probes of the structure of the protein. We have developed a general procedure whereby the ionization constant and chemica...
42
pubmed23n0001_18
Modification of arginine and lysine in proteins with 2,4-pentanedione.
Primary amines react with 2,4-pentanedione at pH 6-9 to form enamines, N-alkyl-4-amino-3-penten-2-ones. The latter compounds readily regenerate the primary amine at low pH or on treatment with hydroxylamine. Guanidine and substituted guanidines react with 2,4-pentanedione to form N-substituted 2-amino-4,6-dimethylpyrim...
Modification of arginine and lysine in proteins with 2,4-pentanedione. Primary amines react with 2,4-pentanedione at pH 6-9 to form enamines, N-alkyl-4-amino-3-penten-2-ones. The latter compounds readily regenerate the primary amine at low pH or on treatment with hydroxylamine. Guanidine and substituted guanidines reac...
43
pubmed23n0001_19
The origin of the alkaline inactivation of pepsinogen.
Above pH 8.5, pepsinogen is converted into a form which cannot be activated to pepsin on exposure to low pH. Intermediate exposure to neutral pH, however, returns the protein to a form which can be activated. Evidence is presented for a reversible, small conformational change in the molecule, distinct from the unfoldin...
The origin of the alkaline inactivation of pepsinogen. Above pH 8.5, pepsinogen is converted into a form which cannot be activated to pepsin on exposure to low pH. Intermediate exposure to neutral pH, however, returns the protein to a form which can be activated. Evidence is presented for a reversible, small conformati...
44
pubmed23n0001_20
Bovine liver dihydrofolate reductase: purification and properties of the enzyme.
A purification procedure is reported for obtaining bovine liver dihydrofolate reductase in high yield and amounts of 100-200 mg. A key step in the procedure is the use of an affinity gel prepared by coupling pteroyl-L-lysine to Sepharose. The purified reductase has a specific activity of about 100 units/mg and is homog...
Bovine liver dihydrofolate reductase: purification and properties of the enzyme. A purification procedure is reported for obtaining bovine liver dihydrofolate reductase in high yield and amounts of 100-200 mg. A key step in the procedure is the use of an affinity gel prepared by coupling pteroyl-L-lysine to Sepharose. ...
45
pubmed23n0001_21
Purification and properties of Escherichia coli dihydrofolate reductase.
Dihydrofolate reductase has been purified 40-fold to apparent homogeneity from a trimethoprim-resistant strain of Escherichia coli (RT 500) using a procedure that includes methotrexate affinity column chromatography. Determinations of the molecular weight of the enzyme based on its amino acid composition, sedimentation...
Purification and properties of Escherichia coli dihydrofolate reductase. Dihydrofolate reductase has been purified 40-fold to apparent homogeneity from a trimethoprim-resistant strain of Escherichia coli (RT 500) using a procedure that includes methotrexate affinity column chromatography. Determinations of the molecula...
46
pubmed23n0001_22
The influence of pH on the interaction of inhibitors with triosephosphate isomerase and determination of the pKa of the active-site carboxyl group.
Ionization effects on the binding of the potential transition state analogues 2-phosphoglycolate and 2-phosphoglycolohydroxamate appear to be attributable to the changing state of ionization of the ligands themselves, therefore it is unnecessary to postulate the additional involvement of an ionizing residue at the acti...
The influence of pH on the interaction of inhibitors with triosephosphate isomerase and determination of the pKa of the active-site carboxyl group. Ionization effects on the binding of the potential transition state analogues 2-phosphoglycolate and 2-phosphoglycolohydroxamate appear to be attributable to the changing s...
47
pubmed23n0001_23
Monoanion inhibition and 35Cl nuclear magnetic resonance studies of renal dipeptidase.
Kinetic analyses of monoanion inhibition and 15Cl nuclear magnetic resonance at 5.88 MHz were employed to study monoanion interactions with the zinc metalloenzyme, renal dipeptidase. The enzyme-catalyzed hydrolysis of glycyldehydrophenylalanine exhibited competitive inhibition when the reaction rate was determined in t...
Monoanion inhibition and 35Cl nuclear magnetic resonance studies of renal dipeptidase. Kinetic analyses of monoanion inhibition and 15Cl nuclear magnetic resonance at 5.88 MHz were employed to study monoanion interactions with the zinc metalloenzyme, renal dipeptidase. The enzyme-catalyzed hydrolysis of glycyldehydroph...
48
pubmed23n0001_24
The interaction of bovine erythrocyte superoxide dismutase with hydrogen peroxide: inactivation of the enzyme.
Bovine erythrocyte superoxide dismutase was slowly and irreversibly inactivated by hydrogen peroxide. The rate of this inactivation was directly dependent upon the concentrations of both H2O2 and of enzyme, and its second-order rate constant at pH 10.0 and 25 degrees was 6.7 M-1 sec-1. Inactivation was preceded by a bl...
The interaction of bovine erythrocyte superoxide dismutase with hydrogen peroxide: inactivation of the enzyme. Bovine erythrocyte superoxide dismutase was slowly and irreversibly inactivated by hydrogen peroxide. The rate of this inactivation was directly dependent upon the concentrations of both H2O2 and of enzyme, an...
49
pubmed23n0001_25
Circular dichroism and fluorescence studies of homogeneous antibodies to type III pneumococcal polysaccharide.
The near-ultraviolet circular dichroism (CD) of three homogeneous anti-type III pneumococcal antibodies in the absence and the presence of the specific hexasaccharide ligand was studied. In addition recombinations and hybridizations of H and L chains derived from two of these antibodies were carried out and the CD spec...
Circular dichroism and fluorescence studies of homogeneous antibodies to type III pneumococcal polysaccharide. The near-ultraviolet circular dichroism (CD) of three homogeneous anti-type III pneumococcal antibodies in the absence and the presence of the specific hexasaccharide ligand was studied. In addition recombinat...
50
pubmed23n0001_26
Conformational changes induced in a homogeneous anti-type III pneumococcal antibody by oligosaccharides of increasing size.
The circular polarization of luminescence (CPL) emitted by tryptophan residues was used as a sensitive probe for measuring ligand-induced structural changes in a homogeneous type III pneumococcal antibody. A series of oligosaccharide ligands of increasing size derived from type III polysaccharide by partial acid hydrol...
Conformational changes induced in a homogeneous anti-type III pneumococcal antibody by oligosaccharides of increasing size. The circular polarization of luminescence (CPL) emitted by tryptophan residues was used as a sensitive probe for measuring ligand-induced structural changes in a homogeneous type III pneumococcal ...
51
pubmed23n0001_27
Evidence of the involvement of a 50S ribosomal protein in several active sites.
The functional role of the Bacillus stearothermophilus 50S ribosomal protein B-L3 (probably homologous to the Escherichia coli protein L2) was examined by chemical modification. The complex [B-L3-23S RNA] was photooxidized in the presence of rose bengal and the modified protein incorporated by reconstitution into 50S r...
Evidence of the involvement of a 50S ribosomal protein in several active sites. The functional role of the Bacillus stearothermophilus 50S ribosomal protein B-L3 (probably homologous to the Escherichia coli protein L2) was examined by chemical modification. The complex [B-L3-23S RNA] was photooxidized in the presence o...
52
pubmed23n0001_28
The interaction of phospholipase A2 with micellar interfaces. The role of the N-terminal region.
The localization of the previously postulated interface recognition site (IRS) in porcine pancreatic phospholipase A2, required for a specific interaction between the enzyme and organized lipid-water interfaces, was investigated by ultraviolet difference spectroscopy, by measurements of the intrinsic fluorescence of th...
The interaction of phospholipase A2 with micellar interfaces. The role of the N-terminal region. The localization of the previously postulated interface recognition site (IRS) in porcine pancreatic phospholipase A2, required for a specific interaction between the enzyme and organized lipid-water interfaces, was investi...
53
pubmed23n0001_29
Phospholipase A2 as a probe of phospholipid distribution in erythrocyte membranes. Factors influencing the apparent specificity of the reaction.
The action of snake venom phospholipases A2 in intact human erythrocytes was investigated in detail. The basis phospholipase from Agkistrodon halys blomhifii was found to induce both hydrolysis of membrane phospholipids and total cell hemolysis under certain experimental conditions. The hydrolytic action of the basic e...
Phospholipase A2 as a probe of phospholipid distribution in erythrocyte membranes. Factors influencing the apparent specificity of the reaction. The action of snake venom phospholipases A2 in intact human erythrocytes was investigated in detail. The basis phospholipase from Agkistrodon halys blomhifii was found to indu...
54
pubmed23n0001_30
Subunit interactions in yeast glyceraldehyde-3-phosphate dehydrogenase.
The spontaneous inactivation of yeast glyceraldehyde-3-phosphate dehydrogenase was found to fit a simple two-state model at pH 8.5 and 25 degrees. The first step is a relatively rapid dissociation of the tetramer to dimers with the equilibrium largely in favor of the tetramer. In the absence of NAD+ the dimer inactivat...
Subunit interactions in yeast glyceraldehyde-3-phosphate dehydrogenase. The spontaneous inactivation of yeast glyceraldehyde-3-phosphate dehydrogenase was found to fit a simple two-state model at pH 8.5 and 25 degrees. The first step is a relatively rapid dissociation of the tetramer to dimers with the equilibrium larg...
55
pubmed23n0001_31
Kinetic light scattering studies on the dissociation of hemoglobin from Lumbricus terrestris.
The kinetics of the pH-induced dissociation of the 3 X 10(6) mol wt hemoglobin from Lumbricus terrestris (the earthworm) have been studied in a light-scattering stopped-flow apparatus. The ligand dependent dissociation data were fit well by a simple sequential model. The data for CO and oxyhemoglobin are consistent wit...
Kinetic light scattering studies on the dissociation of hemoglobin from Lumbricus terrestris. The kinetics of the pH-induced dissociation of the 3 X 10(6) mol wt hemoglobin from Lumbricus terrestris (the earthworm) have been studied in a light-scattering stopped-flow apparatus. The ligand dependent dissociation data we...
56
pubmed23n0001_32
The reversible reduction of horse metmyoglobin by the iron(II) complex of trans-1,2-diaminocyclohexane-N,N,N,n-tetraacetate.
The reduction of metmyoglobin by the iron(II) complex of trans-1,2-diaminocyclohexane-N,N,N'N'-tetraacetate (FeCDTA2-) has been investigated. The equilibrium constant, measured spectrophotometrically, is 0.21 with a resulting reduction potential of 0.050 V for Mb0. The rate constant for the reduction is 28 M-1 sec-1 wi...
The reversible reduction of horse metmyoglobin by the iron(II) complex of trans-1,2-diaminocyclohexane-N,N,N,n-tetraacetate. The reduction of metmyoglobin by the iron(II) complex of trans-1,2-diaminocyclohexane-N,N,N'N'-tetraacetate (FeCDTA2-) has been investigated. The equilibrium constant, measured spectrophotometric...
57
pubmed23n0001_33
Constitution and properties of axonal membranes of crustacean nerves.
The purification of axonal membranes of crustaceans was followed by measuring enrichment in [3H]tetrodotoxin binding capacity and in Na+, K+-ATPase activity. A characteristic of these membranes is their high content of lipids and their low content of protein as compared to other types of plasmatic membranes. The axonal...
Constitution and properties of axonal membranes of crustacean nerves. The purification of axonal membranes of crustaceans was followed by measuring enrichment in [3H]tetrodotoxin binding capacity and in Na+, K+-ATPase activity. A characteristic of these membranes is their high content of lipids and their low content of...
58
pubmed23n0001_34
Regulation of nitrogen fixation. Nitrogenase-derepressed mutants of Klebsiella pneumoniae.
1. A new procedure is described for selecting nitrogenase-derepressed mutants based on the method of Brenchley et al. (Brenchley, J.E., Prival, M.J. and Magasanik, B. (1973) J. Biol. Chem. 248, 6122-6128) for isolating histidase-constitutive mutants of a non-N2-fixing bacterium. 2. Nitrogenase levels of the new mutants...
Regulation of nitrogen fixation. Nitrogenase-derepressed mutants of Klebsiella pneumoniae. 1. A new procedure is described for selecting nitrogenase-derepressed mutants based on the method of Brenchley et al. (Brenchley, J.E., Prival, M.J. and Magasanik, B. (1973) J. Biol. Chem. 248, 6122-6128) for isolating histidase-...
59
pubmed23n0001_35
The reaction between the superoxide anion radical and cytochrome c.
1. The superoxide anion radical (O2-) reacts with ferricytochrome c to form ferrocytochrome c. No intermediate complexes are observable. No reaction could be detected between O2- and ferrocytochrome c. 2. At 20 degrees C the rate constant for the reaction at pH 4.7 to 6.7 is 1.4-10(6) M-1. S -1 and as the pH increases ...
The reaction between the superoxide anion radical and cytochrome c. 1. The superoxide anion radical (O2-) reacts with ferricytochrome c to form ferrocytochrome c. No intermediate complexes are observable. No reaction could be detected between O2- and ferrocytochrome c. 2. At 20 degrees C the rate constant for the react...
60
pubmed23n0001_36
Identification of the 120 mus phase in the decay of delayed fluorescence in spinach chloroplasts and subchloroplast particles as the intrinsic back reaction. The dependence of the level of this phase on the thylakoids internal pH.
After a 500 mus laser flash a 120 mus phase in the decay of delayed fluorescence is visible under a variety of circumstances in spinach chloroplasts and subchloroplast particles enriched in Photosystem II prepared by means of digitonin. The level of this phase is high in the case of inhibition of oxygen evolution at th...
Identification of the 120 mus phase in the decay of delayed fluorescence in spinach chloroplasts and subchloroplast particles as the intrinsic back reaction. The dependence of the level of this phase on the thylakoids internal pH. After a 500 mus laser flash a 120 mus phase in the decay of delayed fluorescence is visib...
61
pubmed23n0001_37
Light-induced changes of absorbance and electron spin resonance in small photosystem II particles.
Photosystem II reaction center components have been studied in small system II particles prepared with digitonin. Upon illumination the reduction of the primary acceptor was indicated by absorbance changes due to the reduction of a plastoquinone to the semiquinone anion and by a small blue shifts of absorption bands ne...
Light-induced changes of absorbance and electron spin resonance in small photosystem II particles. Photosystem II reaction center components have been studied in small system II particles prepared with digitonin. Upon illumination the reduction of the primary acceptor was indicated by absorbance changes due to the redu...
62
pubmed23n0001_38
Enzymic reactions of fatty acid hydroperoxides in extracts of potato tuber. II. Conversion of 9- and 13-hydroperoxy-octadecadienoic acids to monohydroxydienoic acid, epoxyhydroxy- and trihydroxymonoenoic acid derivatives.
1. Crude extracts and partially purified enzyme preparations from potato tubers catalyse, at pH 5-7, the conversion of linoleic acid hydroperoxides to a range of oxygenated fatty acid derivatives. 2. 9-D- and 13-L-hydroperoxide isomers are converted at similar rates to equivalent (isomeric) products. 3. The major produ...
Enzymic reactions of fatty acid hydroperoxides in extracts of potato tuber. II. Conversion of 9- and 13-hydroperoxy-octadecadienoic acids to monohydroxydienoic acid, epoxyhydroxy- and trihydroxymonoenoic acid derivatives. 1. Crude extracts and partially purified enzyme preparations from potato tubers catalyse, at pH 5-...
63
pubmed23n0001_39
Partial purification and properties of microsomal phosphatidate phosphohydrolase from rat liver.
Microsomal phosphatidate phosphohydrolase (phosphatidate phosphatase EC 3.1.3.4) was solubilized and fractionated to yield at least two distinct enzymatically active fractions. One, denoted FA, was non-specific, had a relatively high Km for phosphatidic acid and was insensitive to inhibition by diacylglycerol. The seco...
Partial purification and properties of microsomal phosphatidate phosphohydrolase from rat liver. Microsomal phosphatidate phosphohydrolase (phosphatidate phosphatase EC 3.1.3.4) was solubilized and fractionated to yield at least two distinct enzymatically active fractions. One, denoted FA, was non-specific, had a relat...
64
pubmed23n0001_40
Bile acids. XLVII. 12alpha-Hydroxylation of precursors of allo bile acids by rabbit liver microsomes.
Rabbit liver microsomal preparations fortified with 0.1 mM NADPH effectively promote hydroxylation of [3beta-3H]- or [24-14C]allochenodeoxycholic acid or [5alpha,6alpha-3H2]5alpha-cholestane-3alpha,7alpha-diol to their respective 12alpha-hydroxyl derivatives in yields of about 25 or 65% in 60 min. Minor amounts of othe...
Bile acids. XLVII. 12alpha-Hydroxylation of precursors of allo bile acids by rabbit liver microsomes. Rabbit liver microsomal preparations fortified with 0.1 mM NADPH effectively promote hydroxylation of [3beta-3H]- or [24-14C]allochenodeoxycholic acid or [5alpha,6alpha-3H2]5alpha-cholestane-3alpha,7alpha-diol to their...
65
pubmed23n0001_41
Partial purification and properties of a phenobarbital-induced aldehyde dehydrogenase of rat liver.
Properties of the phenobarbital induced cytoplasmic aldehyde dehydrogenase (EC 1.2.1.3) have been studied in rat liver. 7-12-Fold higher levels were seen in the cytoplasmic activities after phenobarbital treatment in reactor compared to non-reactor animals with high concentrations of acetaldehyde (18 mM) and propionald...
Partial purification and properties of a phenobarbital-induced aldehyde dehydrogenase of rat liver. Properties of the phenobarbital induced cytoplasmic aldehyde dehydrogenase (EC 1.2.1.3) have been studied in rat liver. 7-12-Fold higher levels were seen in the cytoplasmic activities after phenobarbital treatment in rea...
66
pubmed23n0001_42
Cholinesterases from plant tissues. VI. Preliminary characterization of enzymes from Solanum melongena L. and Zea mays L.
Enzymes capable of hydrolyzing esters of thiocholine have been assayed in extracts of Solanum melongena L. (eggplant) and Zea Mays L. (corn). The enzymes from both species are inhibited by the anti-cholinesterases neostigmine, physostigmine, and 284c51 and by AMO-1618, a plant growth retardant and they both have pH opt...
Cholinesterases from plant tissues. VI. Preliminary characterization of enzymes from Solanum melongena L. and Zea mays L. Enzymes capable of hydrolyzing esters of thiocholine have been assayed in extracts of Solanum melongena L. (eggplant) and Zea Mays L. (corn). The enzymes from both species are inhibited by the anti-...
67
pubmed23n0001_43
Behavior of soluble and immobilized acid phosphatase in hydro-organic media.
The hydrolysis of p-nitrophenyl phosphate by wheat germ acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) has been investigated in mixtures of aqueous buffers with acetone, dioxane and acetonitrile. The enzyme was either in free solution or immobilized on a pellicular support which consisted of ...
Behavior of soluble and immobilized acid phosphatase in hydro-organic media. The hydrolysis of p-nitrophenyl phosphate by wheat germ acid phosphatase (orthophosphoric monoester phosphohydrolase, EC 3.1.3.2) has been investigated in mixtures of aqueous buffers with acetone, dioxane and acetonitrile. The enzyme was eithe...
68
pubmed23n0001_44
Purification and some enzymatic properties of the chitosanase from Bacillus R-4 which lyses Rhizopus cell walls.
A strain of Bacillus sp (Bacillus R-4) produces a protease and a carbohydrolase both of which have the ability to lyse Rhizopus cell walls. Of the enzymes, the carbohydrolase has been purified to an ultracentrifugally and electrophoretically homogeneous state, and identified as a chitosanase. The enzyme was active on g...
Purification and some enzymatic properties of the chitosanase from Bacillus R-4 which lyses Rhizopus cell walls. A strain of Bacillus sp (Bacillus R-4) produces a protease and a carbohydrolase both of which have the ability to lyse Rhizopus cell walls. Of the enzymes, the carbohydrolase has been purified to an ultracen...
69
pubmed23n0001_45
Specificity studies on alpha-mannosidases using oligosaccharides from mannosidosis urine as substrates.
Oligosaccharides containing terminal non-reducing alpha(1 leads to 2)-, alpha(1 leads to 3)-, and alpha(1 leads to 6)-linked mannose residues, isolated from human and bovine mannosidosis urines were used as substrates to test the specificities of acidic alpha-mannosidases isolated from human and bovine liver. The enzym...
Specificity studies on alpha-mannosidases using oligosaccharides from mannosidosis urine as substrates. Oligosaccharides containing terminal non-reducing alpha(1 leads to 2)-, alpha(1 leads to 3)-, and alpha(1 leads to 6)-linked mannose residues, isolated from human and bovine mannosidosis urines were used as substrate...
70
pubmed23n0001_46
Calcium-stimulated adenosine triphosphatase in the microsomal fraction of tooth germ from porcine fetus.
The characterization and localization of a Ca(2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) in the tooth germ of the porcine fetus are reported. This enzyme, a microsome fraction, is preferentially activated by Ca(2+). In the presence of 0.5 mM ATP, maximal enzyme activity is obtained at 0.5--1.0 mM CaCl2. The maximal ...
Calcium-stimulated adenosine triphosphatase in the microsomal fraction of tooth germ from porcine fetus. The characterization and localization of a Ca(2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) in the tooth germ of the porcine fetus are reported. This enzyme, a microsome fraction, is preferentially activated by Ca(2...
71
pubmed23n0001_47
Preparation and characterization of an enzymatically active immobilized derivative of myosin.
Purified skeletal muscle myosin (EC 3.6.1.3) has been covalently bound to Sepharose 4B by the cyanogen bromide procedure. The resulting complex, Sepharose-Myosin, possesses adenosine triphosphatase activity and is relatively stable for long periods of time. Under optimal binding conditions, approximately 33% of the spe...
Preparation and characterization of an enzymatically active immobilized derivative of myosin. Purified skeletal muscle myosin (EC 3.6.1.3) has been covalently bound to Sepharose 4B by the cyanogen bromide procedure. The resulting complex, Sepharose-Myosin, possesses adenosine triphosphatase activity and is relatively s...
72
pubmed23n0001_48
Radioactive labeling and location of specific thiol groups in myosin from fast, slow and cardiac muscles.
1. Based on incorporation of radioactively labeled N-ethylmaleimide, the readily reactive thiol groups of isolated myosin (EC 3.6.1.3) from fast, slow and cardiac muscles could be classified into 3 types. All 3 myosins contain 2 thiol-1, 2 thiol-2 and a variable number of thiol-3 groups per molecule. Both thiol-1 and t...
Radioactive labeling and location of specific thiol groups in myosin from fast, slow and cardiac muscles. 1. Based on incorporation of radioactively labeled N-ethylmaleimide, the readily reactive thiol groups of isolated myosin (EC 3.6.1.3) from fast, slow and cardiac muscles could be classified into 3 types. All 3 myo...
73
pubmed23n0001_49
Yeast glutathione reductase. Studies of the kinetics and stability of the enzyme as a function of pH and salt concentration.
1. The pH dependencies of the apparent Michaelis constant for oxidized glutathione and the apparent turnover number of yeast glutathione reductase (EC 1.6.4.2) have been determined at a fixed concentration of 0.1 mM NADPH in the range pH 4.5--8.0. Between pH 5.5 and 7.6, both of these parameters are relatively constant...
Yeast glutathione reductase. Studies of the kinetics and stability of the enzyme as a function of pH and salt concentration. 1. The pH dependencies of the apparent Michaelis constant for oxidized glutathione and the apparent turnover number of yeast glutathione reductase (EC 1.6.4.2) have been determined at a fixed con...
74
pubmed23n0001_50
Characteristics of the dephosphorylated form of phosphorylase purified from rat liver and measurement of its activity in crude liver preparations.
The phosphorylated form of liver glycogen phosphorylase (alpha-1,4-glucan : orthophosphate alpha-glucosyl-transferase, EC 2.4.1.1) (phosphorylase a) is active and easily measured while the dephosphorylated form (phosphorylase b), in contrast to the muscle enzyme, has been reported to be essentially inactive even in the...
Characteristics of the dephosphorylated form of phosphorylase purified from rat liver and measurement of its activity in crude liver preparations. The phosphorylated form of liver glycogen phosphorylase (alpha-1,4-glucan : orthophosphate alpha-glucosyl-transferase, EC 2.4.1.1) (phosphorylase a) is active and easily mea...
75
pubmed23n0001_51
Multiple forms of casein kinase from rabbit erythrocytes.
Two rabbit erythrocyte casein kinases, GTP:casein kinase I and GTP:casein kinase II, have been purified 29 000- and 47 000-fold, respectively. Studies employing sucrose density gradient centrifugation indicate that kinase I has a molecular weight of about 9.5 - 10(5) (25 S) and kinase II about 1.4 - 10(6) (32 S). These...
Multiple forms of casein kinase from rabbit erythrocytes. Two rabbit erythrocyte casein kinases, GTP:casein kinase I and GTP:casein kinase II, have been purified 29 000- and 47 000-fold, respectively. Studies employing sucrose density gradient centrifugation indicate that kinase I has a molecular weight of about 9.5 - ...
76
pubmed23n0001_52
Kinetic studies and effects of anions on creatine phosphokinase from skeletal muscle of rhesus monkey (Macaca mulatta).
A purification procedure for creatine kinase (EC 2.7.3.2) from muscle of the monke35--170 muequiv H+/mg protein per min at 30 degrees C and a yield of approx. 0.5 g/kg muscle. Assuming equilibrium kinetics, synergistic binding of substrates at one catalytic site is found for both the forward and back reactions. Kinetic...
Kinetic studies and effects of anions on creatine phosphokinase from skeletal muscle of rhesus monkey (Macaca mulatta). A purification procedure for creatine kinase (EC 2.7.3.2) from muscle of the monke35--170 muequiv H+/mg protein per min at 30 degrees C and a yield of approx. 0.5 g/kg muscle. Assuming equilibrium kin...
77
pubmed23n0001_53
Studies on rat renal cortical cell kallikrein. I. Separation and measurement.
A technique has been developed to separate and measure kallikrein in a heterogeneous population of rat renal cortical cells in suspension. After rat kidneys were perfused in situ in anaesthetized rats, viable, counted cortical cell suspensions were obtained. Cells were suspended in a sucrose/Tris buffer containing 0.5%...
Studies on rat renal cortical cell kallikrein. I. Separation and measurement. A technique has been developed to separate and measure kallikrein in a heterogeneous population of rat renal cortical cells in suspension. After rat kidneys were perfused in situ in anaesthetized rats, viable, counted cortical cell suspension...
78
pubmed23n0001_54
Studies on electron transfer between mercury electrode and hemoprotein.
The electrochemical behaviour of ferricytochrome c, metmyoglobin and methemoglobin was studied using d.c., a.c. and differential pulse polarography, and controlled potential electrolysis. 1. The three hemoproteins yield d.c. polarographic steps, and peaks in differential pulse polarograms, the height of which is propor...
Studies on electron transfer between mercury electrode and hemoprotein. The electrochemical behaviour of ferricytochrome c, metmyoglobin and methemoglobin was studied using d.c., a.c. and differential pulse polarography, and controlled potential electrolysis. 1. The three hemoproteins yield d.c. polarographic steps, an...
79
pubmed23n0001_55
The binding of organic phosphates to human methaemoglobin A. Perturbation of the polymerization of proteins by effectors.
Theory is presented relating to the binding of an effector to two states of a protein acceptor coexisting in equilibrium. The problem is treated in terms of the four possible cases which specify relations between numbers of binding sites and intrinsic binding constants relevant to the acceptor states. It is shown that ...
The binding of organic phosphates to human methaemoglobin A. Perturbation of the polymerization of proteins by effectors. Theory is presented relating to the binding of an effector to two states of a protein acceptor coexisting in equilibrium. The problem is treated in terms of the four possible cases which specify rel...
80
pubmed23n0001_56
N-terminal spin label studies of hemoglobin, Ligand and pH dependence.
Human hemoglobin was spin labeled with 4-isothiocanato-2,2,6,6-tetramethyl-piperdinooxyl, which is known to bind specifically to the N-terminal alpha-amino groups of proteins and slightly to the reactive sulfhydryl groups. Electron spin resonance (ESR) analysis indicated a partially resolved five-line spectrum, suggest...
N-terminal spin label studies of hemoglobin, Ligand and pH dependence. Human hemoglobin was spin labeled with 4-isothiocanato-2,2,6,6-tetramethyl-piperdinooxyl, which is known to bind specifically to the N-terminal alpha-amino groups of proteins and slightly to the reactive sulfhydryl groups. Electron spin resonance (E...
81
pubmed23n0001_57
The behavior of holo- and apo-forms of bovine superoxide dismutase at low pH.
1. Holo-superoxide dismutase from bovine erythrocytes has been shown to undergo a reversible structural modification in the pH 3-5 range. 2. The spectral alterations observed on changing from neutrality to pH 2 were: a slight attenuation of the 680 nm absorbance; the loss of the 450 nm shoulder, apparent in the optical...
The behavior of holo- and apo-forms of bovine superoxide dismutase at low pH. 1. Holo-superoxide dismutase from bovine erythrocytes has been shown to undergo a reversible structural modification in the pH 3-5 range. 2. The spectral alterations observed on changing from neutrality to pH 2 were: a slight attenuation of t...
82
pubmed23n0001_58
Mechanical precipitation of hemoglobin köln.
Hb Köln (beta 98 Val leads to Met) was found to precipitate rapidly during mechanical shaking. The rate of precipitation of Hb Köln is 5-6 times faster than that of Hb S. The kinetics of precipitation of the patient's hemolysate, which is a mixture of Hb Köln and Hb A, showed a biphasic curve indicating that Hb Köln pr...
Mechanical precipitation of hemoglobin köln. Hb Köln (beta 98 Val leads to Met) was found to precipitate rapidly during mechanical shaking. The rate of precipitation of Hb Köln is 5-6 times faster than that of Hb S. The kinetics of precipitation of the patient's hemolysate, which is a mixture of Hb Köln and Hb A, showe...
83
pubmed23n0001_59
Physical properties and subunits of Haemopis grandis erythrocruorin.
The erythrocruorin of the leech Haemopis grandis possessed an S20,w of 57 S at neutral pH, its isoelectric point at pH 6.0 and exhibited a slightly sigmoid oxygenation curve with n approximately 2.1 and P50 = 11.2 mm at pH 7.4. A minimum molecular weight of 24000 +/- 1500 per heme group was determined from the iron and...
Physical properties and subunits of Haemopis grandis erythrocruorin. The erythrocruorin of the leech Haemopis grandis possessed an S20,w of 57 S at neutral pH, its isoelectric point at pH 6.0 and exhibited a slightly sigmoid oxygenation curve with n approximately 2.1 and P50 = 11.2 mm at pH 7.4. A minimum molecular wei...
84
pubmed23n0001_60
Myosin from arterial smooth muscle: isolation following actin depolymerization.
The contractile proteins from arterial smooth muscle are highly soluble, and can be extracted at I = 0.05. However, they can be precipitated by a prolonged dialysis at pH 6 to give an actomyosin with a high, although variable, actin:myosin ratio. The sedimentation behavior of this actomyosin at high ionic strength was ...
Myosin from arterial smooth muscle: isolation following actin depolymerization. The contractile proteins from arterial smooth muscle are highly soluble, and can be extracted at I = 0.05. However, they can be precipitated by a prolonged dialysis at pH 6 to give an actomyosin with a high, although variable, actin:myosin ...
85
pubmed23n0001_61
Hybrids of chemical derivatives of Escherichia coli alkaline phosphatase.
The activities of hybrid dimers of alkaline phosphatase containing two chemically modified subunits have been investigated. One hybrid species was prepared by dissociation and reconstitution of a mixture of two variants produced by chemical modification of the native enzyme with succinic anhydride and tetranitromethane...
Hybrids of chemical derivatives of Escherichia coli alkaline phosphatase. The activities of hybrid dimers of alkaline phosphatase containing two chemically modified subunits have been investigated. One hybrid species was prepared by dissociation and reconstitution of a mixture of two variants produced by chemical modif...
86
pubmed23n0001_62
Some physicochemical properties of hemoglobin-manitoba (alpha2 102Ser replaced by Arg (G9) beta2).
Hb-Manitoba was discovered in 1970 [1] in a Canadian family of British origin. Recently we observed the same variant in a second family, and found that the oxy-derivative of Hb-Manitoba is slightly unstable at 65 degrees C, dissociates less readily at alkaline pH than does Hb-A, and forms asymmetric hybrids with other ...
Some physicochemical properties of hemoglobin-manitoba (alpha2 102Ser replaced by Arg (G9) beta2). Hb-Manitoba was discovered in 1970 [1] in a Canadian family of British origin. Recently we observed the same variant in a second family, and found that the oxy-derivative of Hb-Manitoba is slightly unstable at 65 degrees ...
87
pubmed23n0001_63
The oxygen affinity of haemoglobin Tak, a variant with an elongated beta chain.
The oxygen affinity was investigated of purified Hb Tak, a human haemoglobin variant with elongated beta-chains. A very low P50 value was found which was not influenced by the addition of 2,3 diphosphoglycerate. The n value was 1, indicating non-cooperativity. The oxygen equilibrium curve of the whole blood haemolysate...
The oxygen affinity of haemoglobin Tak, a variant with an elongated beta chain. The oxygen affinity was investigated of purified Hb Tak, a human haemoglobin variant with elongated beta-chains. A very low P50 value was found which was not influenced by the addition of 2,3 diphosphoglycerate. The n value was 1, indicatin...
88
pubmed23n0001_64
Effects of membrane ribonuclease and 3'-nucleotidase on the digestion of polyuridylic acid by rat liver plasma membrane.
1. Fragments of isolated rat liver plasma membrane possess a ribonuclease activity which at pH 7.8 in the presence of 10 mM EDTA can digest polyuridylic acid (poly(U)) and polycytidylic acid (poly(C)) but not polyadenylic acid (poly(A)) and polyguanylic acid (poly(G)). Under these conditions, the membrane preparation d...
Effects of membrane ribonuclease and 3'-nucleotidase on the digestion of polyuridylic acid by rat liver plasma membrane. 1. Fragments of isolated rat liver plasma membrane possess a ribonuclease activity which at pH 7.8 in the presence of 10 mM EDTA can digest polyuridylic acid (poly(U)) and polycytidylic acid (poly(C)...
89
pubmed23n0001_65
Alterations in phospholipid-dependent (Na+ +K+)-ATPase activity due to lipid fluidity. Effects of cholesterol and Mg2+.
The (Na+ +K+)-activated, Mg2+-dependent ATPase from rabbit kidney outer medulla was prepared in a partially inactivated, soluble form depleted of endogenous phospholipids, using deoxycholate. This preparation was reactivated 10 to 50-fold by sonicated liposomes of phosphatidylserine, but not by non-sonicated phosphatid...
Alterations in phospholipid-dependent (Na+ +K+)-ATPase activity due to lipid fluidity. Effects of cholesterol and Mg2+. The (Na+ +K+)-activated, Mg2+-dependent ATPase from rabbit kidney outer medulla was prepared in a partially inactivated, soluble form depleted of endogenous phospholipids, using deoxycholate. This pre...
90
pubmed23n0001_66
Conformational and molecular responses to pH variation of the purified membrane adenosine triphosphatase of Micrococcus lysodeikticus.
A preparation of ATPase from the membranes of Micrococcus lysodeikticus, solubilized and more than 95% pure, showed two main bands in analytical polyacrylamide gel electrophoresis. They did not correspond to isoenzymes because one band could be converted into the other by exposure to a mildly alkaline pH value. The con...
Conformational and molecular responses to pH variation of the purified membrane adenosine triphosphatase of Micrococcus lysodeikticus. A preparation of ATPase from the membranes of Micrococcus lysodeikticus, solubilized and more than 95% pure, showed two main bands in analytical polyacrylamide gel electrophoresis. They...
91
pubmed23n0001_67
Membrane-bound enzymes. III. Protease activity in leucocytes in relation to erythrocyte membranes.
Protease activity was detected in membranes of human bovine erythrocytes prepared by the conventional procedures which include washing and removal of the "buffy layer". The enzyme was extracted by 0.75 M KCNS or (NH4)2SO4 and was activated by 0.4 to 0.5 M of the same salts. Colored, particulate hide powder-azure, memb...
Membrane-bound enzymes. III. Protease activity in leucocytes in relation to erythrocyte membranes. Protease activity was detected in membranes of human bovine erythrocytes prepared by the conventional procedures which include washing and removal of the "buffy layer". The enzyme was extracted by 0.75 M KCNS or (NH4)2SO...
92
pubmed23n0001_68
Polymer concentration dependence of the helix to random coil transition of a charged polypeptide in aqueous salt solution.
The helix to coil transition of poly(L-glutamic acid) was investigated in 0.05 and 0.005 M aqueous potassium chloride solutions by use of potentiometric titration and circular dichroism measurement. Polymer concentration dependence of the transition was observed in the range from 0.006 to 0.04 monomol/e in 0.005 M KG1 ...
Polymer concentration dependence of the helix to random coil transition of a charged polypeptide in aqueous salt solution. The helix to coil transition of poly(L-glutamic acid) was investigated in 0.05 and 0.005 M aqueous potassium chloride solutions by use of potentiometric titration and circular dichroism measurement...
96
pubmed23n0001_69
[Structure formation in interphase adsorption layers of lysozyme at liquid boundaries].
In connection with the modelling of biomembranes regularities of the formation and development of interphase adsorption layers of lysozyme at liquid borders under different conditions and depending on the nature of carbohydrate phase were investigated by the determination of mechanical characteristics of such layers. T...
[Structure formation in interphase adsorption layers of lysozyme at liquid boundaries]. In connection with the modelling of biomembranes regularities of the formation and development of interphase adsorption layers of lysozyme at liquid borders under different conditions and depending on the nature of carbohydrate phas...
93
pubmed23n0001_70
[Relation between fluorescence and circular dichroism of the complex of the fluorescence probe 4-dimethylaminochalcone with serum albumin].
The fluorescence probe(4-dimethylaminochalcone; DMH) was noncovalently linked to human serum albumin (HSA). The variation of pH was due to serum albumin structural changes, which was determined in terms of DMH and HSA fluorescence and CD spectra. Considerable changes of fluorescence and CD spectra were observed at pH 8...
[Relation between fluorescence and circular dichroism of the complex of the fluorescence probe 4-dimethylaminochalcone with serum albumin]. The fluorescence probe(4-dimethylaminochalcone; DMH) was noncovalently linked to human serum albumin (HSA). The variation of pH was due to serum albumin structural changes, which w...
94
pubmed23n0001_71
[Luminescence study of the effect of temperature on the conformational state of fibrinogen].
Results are presented of measuring fibrinogen fluorescence parameters in temperature range of 20-80 degrees C at different pH of the solution. It was found that the temperature increase from 20 to 40 degrees C for solutions with pH of 4,5-9,3 were not accompanied by the conformational changes of fibrinogen macromolecul...
[Luminescence study of the effect of temperature on the conformational state of fibrinogen]. Results are presented of measuring fibrinogen fluorescence parameters in temperature range of 20-80 degrees C at different pH of the solution. It was found that the temperature increase from 20 to 40 degrees C for solutions wit...
95
pubmed23n0001_72
[Combined effects of hypoxia and hypercapnia on the functional state of the respiratory center].
Experiments were conducted on cats under nembutal anesthesia; a study was made of pulse activity of bulbar respiratory neurons, electrical activity of the diaphragm and of the intercostal muscles; pO2, pCO2, pH, arterial blood oxygen saturation were determined in combined action of hypoxia and hypercapnia. When hypoxic...
[Combined effects of hypoxia and hypercapnia on the functional state of the respiratory center]. Experiments were conducted on cats under nembutal anesthesia; a study was made of pulse activity of bulbar respiratory neurons, electrical activity of the diaphragm and of the intercostal muscles; pO2, pCO2, pH, arterial bl...
103
pubmed23n0001_73
[Level of nicotinamide coenzymes in the liver and myocardium of rats poisoned with dichlorethane].
Experiments were conducted on male rats. A study was made of the content of nicotinamide coenzymes in the liver and myocardium 24 hours after the administration of 0.5 ml of dichloroethane into the stomach. In parallel with disturbance of the morphological structure of the liver and of the myocardium, increase in the a...
[Level of nicotinamide coenzymes in the liver and myocardium of rats poisoned with dichlorethane]. Experiments were conducted on male rats. A study was made of the content of nicotinamide coenzymes in the liver and myocardium 24 hours after the administration of 0.5 ml of dichloroethane into the stomach. In parallel wi...
104
pubmed23n0001_74
[Effect of carbidine on conditioned defense reflexes].
Chronic experiments were conducted on rats and rabbits; a study was made of the effect of carbidine on the conditioned defence reflexes in stimulation of the mesencephalic part of the reticular formation. Carbidine prevented the depression of the conditioned defence reflexes caused by stimulation of the mesencephalic p...
[Effect of carbidine on conditioned defense reflexes]. Chronic experiments were conducted on rats and rabbits; a study was made of the effect of carbidine on the conditioned defence reflexes in stimulation of the mesencephalic part of the reticular formation. Carbidine prevented the depression of the conditioned defenc...
105
pubmed23n0001_75
[Level of nicotinamide coenzymes in the myocardium of rats during the effects of methylxanthines (theophylline, theobromine, caffeine) and catecholamines].
It was shown in acute experiments on rats that one hour after an intraperitoneal injection of theophylline (50 mg/kg) there was a decrease in the NAD + NADP content by 19.4%, a tendency to a fall of NAD.H2 + NADP.H2 was expressed, and the total nicotinamide coferment level was reduced. A tendency to decrease NAD + NADP...
[Level of nicotinamide coenzymes in the myocardium of rats during the effects of methylxanthines (theophylline, theobromine, caffeine) and catecholamines]. It was shown in acute experiments on rats that one hour after an intraperitoneal injection of theophylline (50 mg/kg) there was a decrease in the NAD + NADP content...
106
pubmed23n0001_76
Potable water quality in rural Georgetown County.
Drinking water supplies of 161 rural communities, in Georgetown County, South Carolina, were randomly selected for sample collection. The analysis showed that most of the waters were slightly acidic. Low, but acceptable concentrations of chloride, copper, fluoride, sodium, cadmium, nitrate and phosphate were found. A f...
Potable water quality in rural Georgetown County. Drinking water supplies of 161 rural communities, in Georgetown County, South Carolina, were randomly selected for sample collection. The analysis showed that most of the waters were slightly acidic. Low, but acceptable concentrations of chloride, copper, fluoride, sodi...
107
pubmed23n0001_77
The importance of an innervated and intact antrum and pylorus in preventing postoperative duodenogastric reflux and gastritis.
This study has investigated the relationship between duodenogastric reflux, gastritis and certain symptoms 6-12 months after three operations for uncomplicated duodenal ulcer. The operations studied were proximal gastric vagotomy (PGV, 20 cases), truncal vagotomy and pyloroplasty (TV+P, 22 cases) and truncal vagotomy a...
The importance of an innervated and intact antrum and pylorus in preventing postoperative duodenogastric reflux and gastritis. This study has investigated the relationship between duodenogastric reflux, gastritis and certain symptoms 6-12 months after three operations for uncomplicated duodenal ulcer. The operations st...
123
pubmed23n0001_78
Haemoglobin Rahere (beta Lys-Thr): A new high affinity haemoglobin associated with decreased 2, 3-diphosphoglycerate binding and relative polycythaemia.
A new haemoglobin with increased oxygen affinity, beta82 (EF6) lysine leads to threonine (Hb Rahere), was found during the investigation of a patient who was found to have a raised haemoglobin concentration after a routine blood count. The substitution affects one of the 2, 3-diphosphoglycerate binding sites, resulting...
Haemoglobin Rahere (beta Lys-Thr): A new high affinity haemoglobin associated with decreased 2, 3-diphosphoglycerate binding and relative polycythaemia. A new haemoglobin with increased oxygen affinity, beta82 (EF6) lysine leads to threonine (Hb Rahere), was found during the investigation of a patient who was found to ...
124
pubmed23n0001_79
Endoscopic papillotomy and removal of gall stones.
Endoscopic papillotomy was attempted in 59 patients with extrahepatic obstruction of the biliary duct system and was actually performed in 50 patients. A special high-frequency diathermy knife was introduced via a duodenoscope into the terminal common bile duct and the roof of the papilla was incised. In 33 out of 39 p...
Endoscopic papillotomy and removal of gall stones. Endoscopic papillotomy was attempted in 59 patients with extrahepatic obstruction of the biliary duct system and was actually performed in 50 patients. A special high-frequency diathermy knife was introduced via a duodenoscope into the terminal common bile duct and the...
125
pubmed23n0001_80
Inhibitory postsynaptic actions of taurine, GABA and other amino acids on motoneurons of the isolated frog spinal cord.
The actions of glycine, GABA, alpha-alanine, beta-alanine and taurine were studied by intracellular recordings from lumbar motoneurons of the isolated spinal cord of the frog. All amino acids tested produced a reduction in the amplitude of postsynaptic potentials, a blockade of the antidromic action potential and an in...
Inhibitory postsynaptic actions of taurine, GABA and other amino acids on motoneurons of the isolated frog spinal cord. The actions of glycine, GABA, alpha-alanine, beta-alanine and taurine were studied by intracellular recordings from lumbar motoneurons of the isolated spinal cord of the frog. All amino acids tested p...
128
pubmed23n0001_81
The involvement of lysophosphoglycerides in neurotransmitter release; the composition and turnover of phospholipids of synaptic vesicles of guinea-pig cerebral cortex and Torpedo electric organ and the effect of stimulation.
(1) Crude synaptosomal fractions (P2) derived from guinea-pig cerebral cortex were incubated in the presence of 50 mM KCl in a Krebs-glucose medium. Torpedo marmorata electric organs were stimulated electrically in vivo at 5 pulses/sec for 30 min by electrodes placed on the electric lobe. Synaptic vesicles were isolate...
The involvement of lysophosphoglycerides in neurotransmitter release; the composition and turnover of phospholipids of synaptic vesicles of guinea-pig cerebral cortex and Torpedo electric organ and the effect of stimulation. (1) Crude synaptosomal fractions (P2) derived from guinea-pig cerebral cortex were incubated in...
129
pubmed23n0001_82
Cardiac output response to altered acid-base status during diethyl ether anaesthesia.
The effects of acid-base changes on cardiac output during diethyl ether anaesthesia were studied in 25 mongrel dogs prepared by surgically implanting a plastic encased non-ferrous core electromagnetic probe on the ascending aorta. The findings are: (1) Metabolic acidaemia produced only slight decrease in cardiac output...
Cardiac output response to altered acid-base status during diethyl ether anaesthesia. The effects of acid-base changes on cardiac output during diethyl ether anaesthesia were studied in 25 mongrel dogs prepared by surgically implanting a plastic encased non-ferrous core electromagnetic probe on the ascending aorta. The...
132
pubmed23n0001_83
The prevention of autolysis of stored cornea using steroid as a lysosome membrane stabilizer.
Many eyes donated for use in corneal grafting are rejected because of signs of autolysis in the donor material. The purpose of this experimental study was to determine whether hydrocortisone acting as a lysosome membrane stabilizer could prevent or retard autolysis of the corneas under storage, and if so, what was the ...
The prevention of autolysis of stored cornea using steroid as a lysosome membrane stabilizer. Many eyes donated for use in corneal grafting are rejected because of signs of autolysis in the donor material. The purpose of this experimental study was to determine whether hydrocortisone acting as a lysosome membrane stabi...
133
pubmed23n0001_84
Respiratory effects of H+ and dinitrophenol injections into the brain stem subarachnoid space of fetal lambs.
Mock cerebrospinal fluid (pH 5.37-8.38) or 2,4-dinitrophenol (DNP) (0.15-1.5 mg) was injected into the subarachnoid space of the ventral brain stem of exteriorized fetal sheep. Changes in pH on the ventral surface of the medulla did not stimulate respiratory efforts or induce significant cardiovascular changes. The res...
Respiratory effects of H+ and dinitrophenol injections into the brain stem subarachnoid space of fetal lambs. Mock cerebrospinal fluid (pH 5.37-8.38) or 2,4-dinitrophenol (DNP) (0.15-1.5 mg) was injected into the subarachnoid space of the ventral brain stem of exteriorized fetal sheep. Changes in pH on the ventral surf...
134
pubmed23n0001_85
Soil fungistasis: elevation of the exogenous carbon and nitrogen requirements for spore germination by fungistatic volatiles in soils.
Axenic, washed conidia of Fusarium solani f. sp. phaseoli, Aspergillus flavus, and Verticillium albo-atrum were placed on washed Difco purified agar discs along with an inorganic salt solution containing various levels of carbon and nitrogen substrates. These discs were exposed to volatiles from six soils (pH 5.1-8.6)....
Soil fungistasis: elevation of the exogenous carbon and nitrogen requirements for spore germination by fungistatic volatiles in soils. Axenic, washed conidia of Fusarium solani f. sp. phaseoli, Aspergillus flavus, and Verticillium albo-atrum were placed on washed Difco purified agar discs along with an inorganic salt s...
135
pubmed23n0001_86
Nitrofurazone-reducing enzymes in E. coli and their role in drug activation in vivo.
Earlier work showed that Escherichia coli contains at least two enzymes which reduce nitrofurazone and other nitrofuran derivatives. One of these enzymes is lacking in some nitrofurazone-resistant mutant strains. We now report that there are three separable nitrofuran reductases in this organism: reductase I (mol. wt. ...
Nitrofurazone-reducing enzymes in E. coli and their role in drug activation in vivo. Earlier work showed that Escherichia coli contains at least two enzymes which reduce nitrofurazone and other nitrofuran derivatives. One of these enzymes is lacking in some nitrofurazone-resistant mutant strains. We now report that the...
136
pubmed23n0001_87
Enzymatic hydrolysis of agar: purification and characterization of neoagarobiose hydrolase and p-nitrophenyl alpha-galactoside hydrolase.
The mixture of polysaccharides in the gelling component of agar (agarose) is hydrolyzed to D-galactose and 3,6-anhydro-L-galactose by a series of hydrolytic enzymes obtained from Pseudomonas atlantica. The final degradative step in the pathway of agarose decomposition is the hydrolysis of the alpha-linkage in the dissa...
Enzymatic hydrolysis of agar: purification and characterization of neoagarobiose hydrolase and p-nitrophenyl alpha-galactoside hydrolase. The mixture of polysaccharides in the gelling component of agar (agarose) is hydrolyzed to D-galactose and 3,6-anhydro-L-galactose by a series of hydrolytic enzymes obtained from Pse...
137
pubmed23n0001_88
Temperature and pH optima for 21 species of thermophilic and thermotolerant fungi.
A glucose-containing mineral medium supplemented with 0.01% yeast extract is described upon which all the species of thermophilic and thermotolerant fungi tested will grow. Thirteen of the 21 species do not require the yeast extract supplement for growth. Using this solid, supplemented mineral medium, the pH and temper...
Temperature and pH optima for 21 species of thermophilic and thermotolerant fungi. A glucose-containing mineral medium supplemented with 0.01% yeast extract is described upon which all the species of thermophilic and thermotolerant fungi tested will grow. Thirteen of the 21 species do not require the yeast extract supp...
138
pubmed23n0001_89
Physiological differences among isolates of Phytophthora cinnamomi.
Significant differences in amylase, beta-glucosidase, and phosphatase activities were observed among four Phytophthora cinnamomi isolates grown in nutrient-amended sterilized soil for 20 days. Amylase pH optima for the four isolates were within a relatively narrow range; at pH 5.5 each isolate was within 90% of its pea...
Physiological differences among isolates of Phytophthora cinnamomi. Significant differences in amylase, beta-glucosidase, and phosphatase activities were observed among four Phytophthora cinnamomi isolates grown in nutrient-amended sterilized soil for 20 days. Amylase pH optima for the four isolates were within a relat...
139
pubmed23n0001_90
Regulation and properties of an invertase from Clostridium pasteurianum.
An intracellular invertase was induced in cultures of Clostridium pasteurianum utilizing sucrose as its carbon source for growth. This enzyme synthesis could be repressed by the addition of fructose of a sucrose-growing culture. In contrast, invertase activity was not affected by the addition of glucose to sucrose-grow...
Regulation and properties of an invertase from Clostridium pasteurianum. An intracellular invertase was induced in cultures of Clostridium pasteurianum utilizing sucrose as its carbon source for growth. This enzyme synthesis could be repressed by the addition of fructose of a sucrose-growing culture. In contrast, inver...
140
pubmed23n0001_91
Characterization studies on the membrane-bound adenosine triphosphatase (ATPase) of Azotobacter vinelandii.
The adenosinetriphosphatase (ATPase) (EC 3.6.1.3) activity in Azotobacter vinelandii concentrates in the membranous R3 fraction that is directly associated with Azotobacter electron transport function. Sonically disrupted Azotobacter cells were examined for distribution of ATPase activity and the highest specific activ...
Characterization studies on the membrane-bound adenosine triphosphatase (ATPase) of Azotobacter vinelandii. The adenosinetriphosphatase (ATPase) (EC 3.6.1.3) activity in Azotobacter vinelandii concentrates in the membranous R3 fraction that is directly associated with Azotobacter electron transport function. Sonically ...
141
pubmed23n0001_92
Effects of zinc-smelter emissions on forest soil microflora.
Within 2 km of a zinc (Zn) smelter in Palmerton, Pennsylvania, near the Lehigh Water Gap, up to 13.5% Zn by weight has been measured in the O2 horizon of the soil, and up to 8% Zn in the A1 horizon. The total numbers of bacteria, actinomycetes, and fungi (measured by dilution plate counts) were greatly reduced in the m...
Effects of zinc-smelter emissions on forest soil microflora. Within 2 km of a zinc (Zn) smelter in Palmerton, Pennsylvania, near the Lehigh Water Gap, up to 13.5% Zn by weight has been measured in the O2 horizon of the soil, and up to 8% Zn in the A1 horizon. The total numbers of bacteria, actinomycetes, and fungi (mea...
142
pubmed23n0001_93
alpha-Naphthoflavone activation of 6-hydroxymethylbenzo(alpha)pyrene synthetase.
alpha-Naphthoflavone activates the aryl hydroxymethyl synthetase of both the microsomal membrane-bound and soluble enzymes of rat liver and rat lung. The enzyme catalyzes the hydroxymethylation of benzo(alpha)pyrene to the 6-hydroxymethyl derivative.
alpha-Naphthoflavone activation of 6-hydroxymethylbenzo(alpha)pyrene synthetase. alpha-Naphthoflavone activates the aryl hydroxymethyl synthetase of both the microsomal membrane-bound and soluble enzymes of rat liver and rat lung. The enzyme catalyzes the hydroxymethylation of benzo(alpha)pyrene to the 6-hydroxymethyl ...
143
pubmed23n0001_94
The effects of the continuous administration of N,N-dimethyl-4-phenylazoaniline (DAB) on the activities and the inducibilities of some drug-metabolizing enzymes in rat liver.
(1) The effect of feeding a relatively low-protein diet containing 0.06% DAB for 29 weeks on the activity of DAB-azoreductase, nitroreductase (p-nitrobenzoic acid), N-oxidase (N,N-dimethylaniline), N-demethylase (DAB), cytochrome P-450, NADPH-cytochrome c reductase, beta-glucuronidase and arylsulphatase A were studied....
The effects of the continuous administration of N,N-dimethyl-4-phenylazoaniline (DAB) on the activities and the inducibilities of some drug-metabolizing enzymes in rat liver. (1) The effect of feeding a relatively low-protein diet containing 0.06% DAB for 29 weeks on the activity of DAB-azoreductase, nitroreductase (p-...
148
pubmed23n0001_95
Some characteristics of two azoreductase systems in rat liver. Relevance to the activity of 2-[4'-di(2"-bromopropyl)-aminophenylazo]benzoic acid (CB10-252), a compound possessing latent cytotoxic activity.
The system involved in the reduction of 2-[4'-di(2''-bromopropyl) aminophenylazolbenzoic acid (CB10-252), an agent designed for treating primary liver cell cancer, has been demonstrated to be localised mainly in the 108 000 X g supernatant fraction of rat liver homogenate. It is also present in other organs particularl...
Some characteristics of two azoreductase systems in rat liver. Relevance to the activity of 2-[4'-di(2"-bromopropyl)-aminophenylazo]benzoic acid (CB10-252), a compound possessing latent cytotoxic activity. The system involved in the reduction of 2-[4'-di(2''-bromopropyl) aminophenylazolbenzoic acid (CB10-252), an agent...
149
pubmed23n0001_96
Mercury inhibition of avian fatty acid synthetase complex.
(1) Subcutaneous or intra-abdominal injections of 8 mg of HgCl2/100 g body weight markedly depressed hepatic fatty acid synthetase activity of chicks at 1 h post-injection. The depression occurred despite the fact that the chicks continued to eat up until the time they were killed. Under these same conditions, the hepa...
Mercury inhibition of avian fatty acid synthetase complex. (1) Subcutaneous or intra-abdominal injections of 8 mg of HgCl2/100 g body weight markedly depressed hepatic fatty acid synthetase activity of chicks at 1 h post-injection. The depression occurred despite the fact that the chicks continued to eat up until the t...
150
pubmed23n0001_97
[Basic phospholipase of Naja nigricollis venom].
It is confirmed that N. nigricollis venom contains several phospholipases one of these is a basic phospholipase A. This enzyme is toxic for mice when injected intravenously. In vitro it reacts on egg yolk lecithin producing lysolecithin and prevents the phenomenon of blood clotting. An immunological identity has been e...
[Basic phospholipase of Naja nigricollis venom]. It is confirmed that N. nigricollis venom contains several phospholipases one of these is a basic phospholipase A. This enzyme is toxic for mice when injected intravenously. In vitro it reacts on egg yolk lecithin producing lysolecithin and prevents the phenomenon of blo...
151
pubmed23n0001_98
[Spontaneous mortality and vascular lesions in 3 rat strains with different blood pressure levels].
We have observed a high and significant mortality in spontaneously hypertensive rats compared to normotensive and hypotensive controls, in the fifth generation. The hypertensive rats exhibited a high frequency of cerebral haemorrhage and periarteritis nodosa.
[Spontaneous mortality and vascular lesions in 3 rat strains with different blood pressure levels]. We have observed a high and significant mortality in spontaneously hypertensive rats compared to normotensive and hypotensive controls, in the fifth generation. The hypertensive rats exhibited a high frequency of cerebra...
152
pubmed23n0001_99
Effects of decreasing arterial blood pressure on cerebral blood flow in the baboon. Influence of the sympathetic nervous system.
The influence of the sympathetic nervous system on the cerebral circulatory response to graded reductions in mean arterial blood pressure was studied in anesthetized baboons. Cerebral blood flow was measured by the 133Xe clearance method, and arterial blood pressure was decreased by controlled hemorrhage. In normal bab...
Effects of decreasing arterial blood pressure on cerebral blood flow in the baboon. Influence of the sympathetic nervous system. The influence of the sympathetic nervous system on the cerebral circulatory response to graded reductions in mean arterial blood pressure was studied in anesthetized baboons. Cerebral blood f...
153