Question

In which of the following techniques, a packed column is calibrated by applying known molecular weight enzyme to find out the molecular weight of a new enzyme?

(a) Mass spectrometry

(b) Ultracentrifugation

(c) Gel filtration

(d) SDS-gel electrophoresis

The question was asked in final exam.

I would like to ask this question from Determination of Molecular Weight of Enzymes in division Enzyme Extraction and Purification of Enzyme Technology

Answer 1

Right option is (c) Gel filtration

The explanation is: In gel filtration, a packed column is calibrated by applying known molecular weight enzyme and then the volume of buffer required to elute out a protein is determined. The absorbance peak is measured at 280nm for each protein leaving the column. From this, a plot of elution volume versus molecular weight is drawn. Thus the unknown enzyme molecular weight is determined from the plot.