RT Journal Article
SR Electronic
T1 On the estimation errors of <em>K<sub>M</sub></em> and <em>V</em> from time-course experiments using the Michaelis–Menten equation
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 068015
DO 10.1101/068015
A1 Wylie Stroberg
A1 Santiago Schnell
YR 2016
UL http://biorxiv.org/content/early/2016/09/06/068015.abstract
AB The conditions under which the Michaelis–Menten equation accurately captures the steady-state kinetics of a simple enzyme-catalyzed reaction is contrasted with the conditions under which the same equation can be used to estimate parameters, KM and V, from progress curve data. Validity of the underlying assumptions leading to the Michaelis–Menten equation are shown to be necessary, but not sufficient to guarantee accurate estimation of KM and V. Detailed error analysis and numerical “experiments” show the required experimental conditions for the independent estimation of both KM and V from progress curves. A timescale, tQ, measuring the portion of the time course over which the progress curve exhibits substantial curvature provides a novel criterion for accurate estimation of KM and V from a progress curve experiment. It is found that, if the initial substrate concentration is of the same order of magnitude as KM, the estimated values of the KM and V will correspond to their true values calculated from the microscopic rate constants of the corresponding mass-action system, only so long as the initial enzyme concentration is less than KM.