Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

beta–lactamase

play
noun be·ta–lac·ta·mase \ˈbā-tə-ˈlak-tə-ˌmās, -ˌmāz\

Definition of beta–lactamase

  1. :  an enzyme found especially in staphylococcal bacteria that inactivates the penicillins by hydrolyzing them



Origin of beta–lactamase

lactam, a cyclic amide (from International Scientific Vocabulary lact- + amide) + -ase


First Known Use: 1965


Medical Dictionary

beta–lactamase

noun be·ta–lac·ta·mase

Medical Definition of beta–lactamase

  1. :  any of various bacterial enzymes that inactivate beta-lactam antibiotics (such as penicillin and cephalosporin) by hydrolyzing them <When confronted with an antibiotic, a number of disease-causing bacteria will retaliate by making an enzyme called beta-lactamase …—Diana Morgan and Terence Monmaney, Science, July/August 1985> <The most common mechanism of resistance to β-lactam antibiotics is the bacterial production of an enzyme called β-lactamase, which breaks one of the antibiotic's chemical bonds, changing its structure and preventing it from inhibiting the enzyme transpeptidase.—K. C. Nicolaou et al., Scientific American, May 2001> Beta-lactamase was originally used only to refer to bacterial enzymes that inactivated penicillin. As additional types of beta-lactam antibiotics were introduced, other bacterial beta-lactamases were identified. —compare penicillinase



Variants of beta–lactamase

also β–lactamase \-ˈlak-tə-ˌmās, -ˌmāz\play

Seen and Heard

What made you want to look up beta–lactamase? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

the range of perception or understanding

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

alt-5746713d76276

Which of these is a synonym of nonplus?

soothe reduce perplex disapprove
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ