In a small research laboratory at one of Berlin’s municipal hospitals (“Am Urban”) two researchers’ very careful work laid the foundation for enzyme kinetics as a systematic field which formed the basis of modern enzymology:
In 1913, Leonor Michaelis and his coworker Maud L. Menten published a paper on the concept of an affinity constant, by studying the relationship between the rate of formation of products in dependence of the concentrations of an enzyme (invertase) and its substrate at constant and controlled pH (Michaelis, M. and Menten M.L., 1913 ). The best-known outcome of this work was the Michaelis–Menten equation, together with the Michaelis constant. This term was coined by George Briggs and J. B. S. Haldane in 1925 (Briggs, G.E. and Haldane, J.B.S., 1925), whose work on enzyme kinetics led to the steady-state approximation assuming a negligible rate of the change of the enzyme-substrate complex compared to the rates of changes in the concentrations of both the substrate and the product. Since then enzymes have been routinely characterized by applying Michaelis and Menten’s approach and evaluation of enzymatic activities. Over the last hundred years this has allowed mechanistic models to be developed and has led to the discovery of a tremendous number of new metabolic pathways in cells and tissues.
Today, the multi-disciplinary approach of modern enzymology, combining a variety of modern experimental and analytical techniques, leads to the generation of huge amounts of data on enzyme structures and activities that are published in journals and databases. However, the outcome of accessing these comprehensive data resources often fails to meet expectations since the functional enzyme data have often been collected under quite disparate experimental conditions and the details of the assay conditions used are often incompletely described.
 Michaelis, L. and Menten, M.L. (1913) Die Kinetik der Invertinwirkung. Biochem. Z. 49:333-369. Engl. Translation: Goody, R.S. and Johnson, K.A. (2011) The Kinetics of Invertase Action. Biochemistry 50:8264-8269.
 Briggs, G.E. and Haldane, J.B.S. (1925) A note on the kinetics of enzyme action. Biochem. J. 19:338-339.