Quantitative Analysis:  Protein extract from E. coli containing a plasmid that expresses a maltose-binding protein-β-galactosidase fusion protein (100,000 units) is passed over a 1 ml column at 4°C. The column is then washed with 10 column volumes of 20 mM Tris-HCl (pH 7.4), 0.2 M…