IMPROVEMENT OF THE EXTRACTION OF PENICILLIN ACYLASE FROM ESCHERICHIA-COLI-CELLS BY A COMBINED USE OF CHEMICAL METHODS

Several techniques for protein extraction were tested for recovering p enicillin acylase from a recombinant strain of Escherichia coil. These techniques include chemical [guanidine hydrochloride, Triton X-100, e thylenediaminetetraacetic acid (EDTA), ethanol/toluene], physical (son ication, freeze-and-thawing), and enzymatic (lysozyme) treatments. Bes t results were obtained with the combined use of guanidine and EDTA. T his extraction procedure was optimized, and it was found that 95% of t he enzyme was extracted after a 10 mM EDTA plus 10 mM guanidine treatm ent at room temperature for 10 h. The purification factor was 25 when compared to disruption by sonication. This extraction method could avo id purification steps for particular applications. (C) 1994 John Wiley & Sons, Inc.