EXPRESSION, PURIFICATION AND CRYSTALLIZATION OF PENICILLIN-G ACYLASE FROM ESCHERICHIA-COLI ATCC-11105

The penicillin acylase gene (pac) from Escherichia coli ATCC 11105 was cloned into pUC 9 and the resulting vector (pUPA-9), when transformed into E.coli strain 5K, allowed the constitutive overproduction of mature penicillin acylase when grown at 28°C. The enzyme ws purified from the periplasmic fraction of E.coli pUPA-9 by hydrophobic interaction chromatography and anion exchange. Crystals of penicillin acylase were grown in batch using polyethylene glycol 8000 as a precipitant. The crystals (space group P1) diffracted to beyond 2.3 Å. © 1990 Oxford University Press.