Components Affecting the Action of Enzymes

In the development and application of biosensors based on enzymes several factors required for the catalytic process have to be taken into account, which are either directly involved in catalysis or influence the formation of the enzyme-substrate complex. They are designated coenzymes, prosthetic groups, and effectors. 

Function of Some Important Coenzymes and Prosthetic Groups 

Flavin mononucleotide Flavin adenine dinucleotide Heme (cytochromes) 

Prosthetic groups have the same function as coenzymes but are tightly bound to the enzyme. When they are split off, the protein is 

Effectors accelerate (activators) or block (inhibitors) the catalytic process. They are bound to the enzyme rather loosely and may therefore easily dissociate. Many of them are metal ions, e.g. Mg++) Ca++, Zn++, K+) and Na+, which either form stoichiometric complexes with the substrate, stabilize an optimal protein conformation, or effect the association of subunits. These inorganic complements of enzyme reactions are frequently subsumed together with coenzymes as cofactors. 

---