Cofactors are chemical components that associate with proteins and supply properties required for particular enzyme activities. Inorganic iron–sulfur clusters participate in catalysis and electron transfer; cellular assembly machinery forms them on scaffold proteins before insertion into recipient proteins [1][2]. Metal–organic cofactors combine a metal center with an organic ligand, as in molybdenum bound within a pterin-containing catalytic group [3]. Cofactor synthesis itself can require specialized enzymatic reactions, including radical chemistry mediated by iron–sulfur proteins and S-adenosylmethionine [4]. Organic and organometallic cofactors can transfer chemical groups or generate reactive intermediates. Vitamin B12 derivatives, for instance, support methyl-group transfer or radical-mediated rearrangement through distinct chemical forms of the cobalt-containing cofactor. Protein binding positions these components relative to substrates and other catalytic groups [5][6].
- coenzymes
- metallocofactors
- enzyme maturation
- catalytic activity
References
- Roland Lill; Function and Biogenesis of Iron–sulphur Proteins. Nature 2009, 460, 831-838, 10.1038/nature08301.
- Roland Lill; Ulrich Mühlenhoff; Maturation of Iron-Sulfur Proteins in Eukaryotes: Mechanisms, Connected Processes, and Diseases. Annu. Rev. Biochem. 2008, 77, 669-700, 10.1146/annurev.biochem.76.052705.162653.
- Günter Schwarz; Ralf R. Mendel; Markus W. Ribbe; Molybdenum Cofactors, Enzymes and Pathways. Nature 2009, 460, 839-847, 10.1038/nature08302.
- Perry A. Frey; Adrian D. Hegeman; Frank J. Ruzicka; The Radical SAM Superfamily. Crit. Rev. Biochem. Mol. Biol. 2008, 43, 63-88, 10.1080/10409230701829169.
- Ruma Banerjee; Stephen W. Ragsdale; The Many Faces of Vitamin B12: Catalysis by Cobalamin-Dependent Enzymes. Annu. Rev. Biochem. 2003, 72, 209-247, 10.1146/annurev.biochem.72.121801.161828.
- Bradley J. Landgraf; Erin L. McCarthy; Squire J. Booker; Radical S-Adenosylmethionine Enzymes in Human Health and Disease. Annu. Rev. Biochem. 2016, 85, 485-514, 10.1146/annurev-biochem-060713-035504.