penicillinase(redirected from penicillinases)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to penicillinases: cephalosporinase
1. Synonym(s): β-lactamase
2. A purified enzyme preparation obtained from cultures of a strain of Bacillus cereus; formerly used to treat slowly developing or delayed penicillin reactions.
penicillinase/pen·i·cil·lin·ase/ (pen″ĭ-sil´ĭ-nās) a β-lactamase preferentially cleaving penicillin.
Any of several beta-lactamase enzymes that cleave the beta-lactam ring in penicillins. Penicillinases are found in many penicillin-resistant bacteria.
an enzyme elaborated by certain bacteria, including many strains of staphylococci, that inactivates penicillin and thereby promotes resistance to the antibiotic. A purified preparation of penicillinase, derived from cultures of saprophytic spore-forming Bacillus cereus, is used in the treatment of adverse reactions to penicillin. Also called beta-lactamase.
penicillinaseAn enzyme present in some bacteria, especially STAPHYLOCOCCI, that inactivates penicillins, by HYDROLYSIS of the beta-lactam bond, so that the organisms possess resistance to the drug. Also known as beta-lactamase.
penicillinaseenzyme inactivating penicillin; produced by some staphylococci
An enzyme produced by many species of bacteria that disrupts the four-membered β-lactam ring of penicillin and cephalosporin groups of antibiotics, destroying their antimicrobial activity.
an enzyme produced by bacteria that inactivates penicillin, thus increasing resistance to the antibiotic; a purified form from Bacillus cereus is used in the treatment of reactions to penicillin.