Measurement of Catalytic Activity Flashcards
Give the measurement of Catalytic Activity (7)
● Increase product concentration - more substrate conversion to product
● Decrease in substrate concentration
● Decrease in coenzyme concentration (NADH) - For
oxidoreductase activity
● Increase in altered coenzyme concentration (Reduced and
oxidized NAD *vice versa)
- Reduced NADH → High absorbance at 340nm
- Oxidized NAD → Decrease absorbance at 340nm
● Dependent on enzyme concentration
● Always performed in zero-order kinetics
● Performed during the linear phase of reaction
What method is the reagents (substrate and enzyme) are combined, the reaction proceeds, the reaction is stopped and the amount of reaction is measured.
Fixed-time (two-point) assay
Multiple measurement at specific time intervals or continuous measurement as absorbance changes
Continuous monitoring or kinetic assays
Target enzyme or enzyme of interest in the px serum
Primary enzyme
Rely on the primary enzyme to proceed
Coupling enzyme
What will happen to the absorbance pattern of sample and reagent when there’s an enzyme reaction
It will increase
An expression of the relationship between the velocity of the enzyme reaction and substrate concentration
Michaelis-Menten Equation
The amount of enzyme that will catalyze the reaction 1 μmol of substrate per minute
IU (EC)
The amount of enzyme that will catalyze the reaction of 1 mol of substrate per second (mol/s)
Kat (SI) - Katal
Quantified by electrophoretic techniques that provides resolution of isoenzymes and isoforms
Electrophoretic Migration (Measurement of enzyme mass)
Theory that the shape of the key (substrate) must fit into the lock (enzyme)
Emil Fisher’s/Lock and Key theory
Based on the substrate binding to the active site of enzyme
Kochland’s Induced Fit theory
