Continuous Enzyme Assay In continuous assays, the course of the reaction is continually followed until completion. Sometimes referred to as 'endpoint assays', enzyme activity is measured via the quantity of substrate consumed, or the amount of product formed during the reaction over a fixed period of time.
Under what conditions would a fixed-time course assay be inappropriate? If you don't know concentration range of salt over which a protein of interest will elute. - fixed time course assay is bad for doing enzyme kinetic mich menson plots. What are the assumptions of the Michaelis-Menten equation?
Enzymatic activity assays are predominately performed by researchers to identify the presence or quantity of a specific enzyme in an organism, tissue, or sample. Examples of such enzymes include α-amylase, catalase, laccase, peroxidase, lysozyme, and reporter enzymes alkaline phosphatase, and luciferase.
fixed-time assay is described that can be adapted. for use with most types ofcolorimetric equipment. The method is evolved from that of C. J. Perret. (Nature 174:1012, 1954) in which iodine strongly. buffered to pH 4.0 is used to stop the reaction.
Disadvantages include difficulties in assay standardization, instability of the enzymes during storage, and misleading results, e.g., due to conditions other than vitamin deficiency leading to low apoenzyme concentrations.
Enzyme assays can be split into two groups according to their sampling method: continuous assays, where the assay gives a continuous reading of activity, and discontinuous assays, where samples are taken, the reaction stopped and then the concentration of substrates/products determined.
The main difference between enzyme activity and specific activity is that enzyme activity is the moles of substrate converted by the enzyme per unit time whereas specific activity is the activity of enzyme per milligram of total enzyme.Jan 16, 2019
The Michaelis constant (KM), defined as the concentration of substrate that is transported at half the maximal velocity (Vmax) of transport, is a measure of the affinity of the transporter for its substrate.