Enzyme

Louis Pasteur was among the first to study enzyme action. He incorrectly hypothesized that the conversion of sugar into alcohol by yeast was catalyzed by "ferments" that could not be separated from living cells. In 1897 the German biochemist Eduard Buchner (1860-1917) isolated the enzymes which catalyze alcoholic fermentation from living yeast cells, represented in the equation:

The early twentieth century saw dramatic advancement in enzyme studies. Emil Fischer (1852-1919) recognized the importance of substrate shape for binding by enzymes. Leonor Michaelis (1875-1949) and Maud Menten introduced a mathematical approach for quantifying enzyme-catalyzed reactions. James Sumner (1887-1955) and John Northrop (1891-1987) were among the first to produce highly ordered enzyme crystals and firmly establish Figure 1. Illustration by Hans & Cassidy. Courtesy of Gale Group. the protein nature of these biological catalysts. In 1937 Hans Krebs (1900-1981) postulated how a series of enzymatic reactions were coordinated in the citric acid cycle for the production of ATP from glucose metabolites. Today, enzymology is a central part of biochemical study.