Activity of penicillin acylase from E-coli in the reversed-micelle system AOT-H2O-octane

The behavior of a penicillin acylase from E. coli was studied in the revers ed-micelle system AOT-H2O-octane. Kinetic studies of the enzymatic hydrolys is of the m-carboxy-p-nitroanilide of phenylacetic acid, titration of the p enicillin acylase active site with an irreversible specific inhibitor (phen ylmethylsulfonyl fluoride), sedimentation analysis at different hydration d egrees, and chemical modification showed that the enzyme loses no more than 20% of its initial activity during 3-4 h in the reversed-micelle systems o f different hydration degrees and retains its catalytically active structur e.