title: The widespread role of non-enzymatic reactions in cellular metabolism.
abstract: Enzymes shape cellular metabolism, are regulated, fast, and for most cases specific. Enzymes do not however prevent the parallel occurrence of non-enzymatic reactions. Non-enzymatic reactions were important for the evolution of metabolic pathways, but are retained as part of the modern metabolic network. They divide into unspecific chemical reactivity and specific reactions that occur either exclusively non-enzymatically as part of the metabolic network, or in parallel to existing enzyme functions. Non-enzymatic reactions resemble catalytic mechanisms as found in all major enzyme classes and occur spontaneously, small molecule (e.g. metal-) catalyzed or light-induced. The frequent occurrence of non-enzymatic reactions impacts on stability and metabolic network structure, and has thus to be considered in the context of metabolic disease, network modeling, biotechnology and drug design.
authors.affiliation: Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, CB2 1GA, Cambridge, UK.
authors.forename: Markus A
authors.initials: MA
authors.lastname: Keller
authors.affiliation: Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, CB2 1GA, Cambridge, UK.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Piedrafita
authors.affiliation: Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, CB2 1GA, Cambridge, UK; MRC National Institute for Medical Research, The Ridgeway, Mill Hill, NW7 1AA, London, UK. Electronic address: mr559@cam.ac.uk.
authors.forename: Markus
authors.initials: M
authors.lastname: Ralser
mesh_terms: D000818:Animals; D055162:Biocatalysis; D016678:Genome; D006801:Humans; D053858:Metabolic Networks and Pathways