Crystalline bacterial penicillinase.

Intermediates in the biosynthesis of bacterial penicillinase.

An evaluation of 12 methods for the demonstration of penicillinase.

Twelve methods for the demonstration of bacterial penicillinase production by strains of Haemophilus influenzae and Staphylococcus aureus are compared, and their suitability for routine clinical laboratory use is evaluated. The acidometric agar plate method is recommended.

Optimal Conditions for Extraction and Purification of Penicillinase Enzyme

Background and Objective: The present study aimed to evaluate the optimum conditions for extracting and purifying penicillinase enzyme. The enzyme source was Bacillus licheniformis 6346 obtained from the Iranian Research Organization for Science and Technology. Materials and Methods: B. licheniformis was cultured in a medium containing mineral salts, nitrogen compounds, and cultured carbon sou...

Regulation of penicillinase synthesis: a mutation in Staphylococcus aureus unlinked to the penicillinase plasmid that reduced penicillinase inducibility.

A mutant of Staphylococcus aureus strain 655 was isolated that is restricted in penicillinase induction. Wild-type plasmids that bear penicillinase determinants could not be fully induced in this mutant, 655par-1; hence, the responsible mutation is not located on the plasmid. Mutant plasmid PI(258)penI443, which produces penicillinase constitutively in wild-type cells, was fully constitutive fo...

The synergistic action of cephalosporin C and benzylpenicillin against a penicillinase-producing strain of Staphylococcus aureus.

Cephalosporin C, a hydrophilic, penicillin-like antibiotic which is insensitive to penicillinase, is much less active than benzylpenicillin against the Oxford strain of Staphylococcus aureus but much more active than benzylpenicillin against a penicillinase-producing strain of S. aureus (D3R). When used together, cephalosporin C and benzylpenicillin act synergistically against S . aureus strain...