History of Enzyme Chemistry
Published Online: 16 MAY 2011
Copyright © 2001 John Wiley & Sons, Ltd. All rights reserved.
How to Cite
Cornish-Bowden, A. 2011. History of Enzyme Chemistry. eLS. .
- Published Online: 16 MAY 2011
Enzymes have been recognized as the catalysts necessary for all physiological processes since the end of the nineteenth century. Before then their study was complicated by arguments over vitalism, which only subsided after Buchner showed that a cell-free extract from yeast could carry out alcoholic fermentation. This led to the flowering of studies of metabolism, and with it a corresponding increase in studies of enzyme catalysis, which were no longer mainly limited to extracellular enzymes such as pepsin. The groundwork for kinetic studies was laid by Henri and by Michaelis and Menten, and understanding of enzyme catalysis was later strengthened when Sumner demonstrated that enzymes could be crystallized. The principal features of three-dimensional structure became known by the 1950s, by which time hundreds of enzymes had been characterized, making it necessary to create a rational classification of reactions catalysed, the basis of the modern EC system.
Nearly all physiological processes are catalysed by proteins known as enzymes.
A few reactions are catalysed by non-protein enzymes based on RNA.
Enzymes are highly specific, with all apart from degradative enzymes extremely restrictive in the reactions they catalyse.
Most enzymes are similar in amino acid sequence to their homologues in other species even between organisms that are phylogenetically very different.
Enzyme catalysis was initially studied primarily by kinetic measurements, but is now based also on three-dimensional structural information derived from crystallography or NMR.