Association for Biology Laboratory Education

Purification of Maltose-Binding Protein from E. coli Periplasm
 



Tested Studies in Laboratory Teaching, 1997, Volume 18

Abstract

By correlating the protein concentration of various fractions from E. coli with the appearance of samples on a gel, this exercise introduces beginning students to the quantitative "bookkeeping" involved in protein purification. A periplasmic fraction is isolated by osmotic shock, and affinity chromatography with amylose resin is used to purify maltose-binding protein. Visualization of fractions by SDS-polyacrylamide gel electrophoresis allows students to evaluate the qualitative success of the purification and to estimate the subunit molecular weight of the purified protein.

Keywords:  cell fractionation, protein purification, affinity chromotography, protein determination, standard curve, SDS-PAGE, osmotic stress

Boston University (1996)