Molybdenum is the 42nd element in the periodic table. It was apparently known to the ancient civilizations, though was often mistaken for lead as they have similar appearances. It does not appear as a pure element in nature or an easily identifiable mineral, hence, there is no alchemical symbol for this element. More is written about molybdenum in its role in earth functions and the water soluble forms are important in the initial development of life on the planet.
There is not a lot of definitive information about how molybdenum is incorporated in the living sphere. It seems that humans and bacteria need trace amounts. It is associated with the sulfur balance in the body and important in liver detoxification. The molybdenum based enzymes are important with this function. They also cleanse nerve cell transmitter molecules and keep the nervous system working in balance.