noun. One of two or more contributing factors.

noun. A substance, such as a metallic ion or coenzyme, that must be associated with an enzyme for the enzyme to function.

noun. a contributing factor

noun. a substance, especially a coenzyme or a metal, that must be present for an enzyme to function

noun. a molecule that binds to and regulates the activity of a protein

noun. the result of a number being divided by one of its factors

noun. a substance (as a coenzyme) that must join with another to produce a given result

"Enzymatic methane production involves the tiny molecule deazaflavin, known as cofactor F0 or cofactor F420."

chemical compound  compound  

adaptor  adenine  adsorber  catalysis  cell-surface