Biomaterial Database

A simple method for calculating Km and V from a single enzyme reaction progress curve. 1977

S L Yun, and C H Suelter

A method of calculating Km and V from a single reaction progress curve is presented. The integrated Michaelis-Menten equation Vt = So + Km 1n(So/S), may be rearranged to the form 1/v = 1/V + Km/VS, where v = (Si - Sj)/deltat = deltaS/deltat and S = (Si - Sj)/ln(Si/Sj) or S is approximated by (Si + Sj)/2.Si and Sj represent substrate concentrations at two points along a reaction progress curve separated by the time interval, deltat. The error resulting from the approximation depends on the magnitude of deltaSi/Si; when deltaSi/Si less than 0.3, the error is insignificant; when deltaSi/Si greater than 0.3, the error becomes significant. Procedures are presented to correct this error. Simulated data and application to the direct spectrophotometric assay of AMP aminohydrolase and the lactate dehydrogenase coupled assay of pyruvate kinase are provided. The method is recommended when routine Km and V values are desired. Compared to the initial rate method, it is faster, requires less substrate, and eliminates pipetting errors.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D004798	Enzymes	Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.	Biocatalyst,Enzyme,Biocatalysts
D005069	Evaluation Studies as Topic	Works about studies that determine the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies.	Critique,Evaluation Indexes,Evaluation Methodology,Evaluation Report,Evaluation Research,Methodology, Evaluation,Pre-Post Tests,Qualitative Evaluation,Quantitative Evaluation,Theoretical Effectiveness,Use-Effectiveness,Critiques,Effectiveness, Theoretical,Evaluation Methodologies,Evaluation Reports,Evaluation, Qualitative,Evaluation, Quantitative,Evaluations, Qualitative,Evaluations, Quantitative,Indexes, Evaluation,Methodologies, Evaluation,Pre Post Tests,Pre-Post Test,Qualitative Evaluations,Quantitative Evaluations,Report, Evaluation,Reports, Evaluation,Research, Evaluation,Test, Pre-Post,Tests, Pre-Post,Use Effectiveness
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor