Also known as β-lactamases, these are enzymes that hydrolyze (break down) the β-lactam ring (portion) of the penicillin molecule’s structure. Some microorganisms (e.g., pathogenic bacteria) have become able to produce these enzymes as a defense to penicillin and cephalosporin antibiotics (drugs).
An enzyme produced by some bacteria that destroys penicillin.
An enzyme produced by some bacteria that inactivates penicillin, used to treat adverse reactions to penicillin.
Enzymic bacterial growth product antagonistic to penicillin, produced abundantly by B. subtilis, but also by many other species which are thereby resistant to penicillin therapy. Penicillinase harvested from selected B. subtilis strains is used to nullify penicillin in blood and other cultures, one unit thereof being that quantity which neutralizes one unit of penicillin.
Enzyme produced by certain bacteria, especially staphylococci strains, that inactivates penicillin and causes resistance to the antibiotic.
An enzymelike substance, produced by some bacteria, that is capable of antagonizing the antibacterial action of penicillin. Purified penicillinase, obtained from a strain of Bacillus cereus, may be used to treat reactions to penicillin. It is also used in diagnostic tests to isolate microorganisms from the blood of patients receiving penicillin.
A bacterial enzyme that inactivates most but not all penicillins.