A ‘hit-and-run’ kinetic mechanism for the analysis enzyme progress curves under low substrate concentrations
نویسندگان
چکیده
For enzymatic progress curves conforming to the Michaelis–Menten mechanism (E + S ES → E + P) under the experimental conditions where the substrate concentration is at least several times smaller than the Michaelis constant, the minimal fitting model cast as a system of numerically integrated differential equations is the simple ‘hit-and-run’ mechanism, E + S → E + P. The best-fit value of single relevant rate constant is identical to the specificity constant, kcat/KM. An illustrative example involves a fluorogenic continuous assay of the matrix metalloprotease MMP12, analyzed by the differential-equation oriented software package DYNAFIT [P. Kuzmic (1996) Anal. Biochem. 237, 260].
منابع مشابه
Analysis of progress curves in enzyme kinetics.
Since Michaelis & Menten (1913) demonstrated that many of the problems encountered by earlier workers in enzyme kinetics could be avoided by measuring initial rates and using kinetic equations in their differential forms, most biochemists have been reluctant to use integrated rate equations. However, confining analysis to the initial linear part of a progress curve wastes much of the available ...
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