In enzymes like peroxidase and catalase, which facilitate the conversion of hydrogen peroxide into water and oxygen, 'haem' functions as the prosthetic group and is integral to the active site of these enzymes.

In contrast, zinc acts as a cofactor in the enzyme carbonic anhydrase.

RuBisCo is noted as the most abundant protein across the biosphere.

Succinate serves as the substrate for the enzyme succinate dehydrogenase.