Stabilization of penicillin G acylase against pH by chemical cross-linking

Kazan D., Ertan H., Erarslan A.

PROCESS BIOCHEMISTRY, vol.31, no.2, pp.135-140, 1996 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 31 Issue: 2
  • Publication Date: 1996
  • Doi Number: 10.1016/0032-9592(95)00038-0
  • Journal Name: PROCESS BIOCHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.135-140
  • Kocaeli University Affiliated: No

Abstract

The effect of pHs between 2.0 and 10.0 on the inactivation kinetics of penicillin G acylase (PGA) obtained from a mutant of Escherichia coli ATCC 11105 and the stabilization of enzyme against pH by chemical cross-linking with dimethyladipimidate (DMA) were studied. The inactivation mechanisms of native and DMA cross-linked PGA both appeared to obey first-order inactivation kinetics during prolonged incubation of enzyme solutions at 40 degrees C and at different pH values. The lowest inactivation rate constants were obtained with both native and DMA cross-linked PGA at pH 7.0. Inactivation rate constants decreased with an increase in pH from 2.0 to 7.0 and then increased again at pH values above 7.0. Chemical cross-linking of PGA by DMA resulted in the stabilization of enzyme against pH. Highest enhancement of pH stabilization (nearly four-fold) was obtained at pH 7.0 and 8.0.