beta-lactamase

noun

be·​ta-lac·​ta·​mase ˈbā-tə-ˈlak-tə-ˌmās How to pronounce beta-lactamase (audio)
-ˌmāz
: any of various bacterial enzymes that inactivate the penicillins and cephalosporins by hydrolyzing them
When confronted with an antibiotic, a number of disease-causing bacteria will retaliate by making an enzyme called beta-lactamaseDiana Morgan and Terence Monmaney

Word History

Etymology

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

First Known Use

1963, in the meaning defined above

Time Traveler
The first known use of beta-lactamase was in 1963

Dictionary Entries Near beta-lactamase

Cite this Entry

“Beta-lactamase.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/beta-lactamase. Accessed 5 Jun. 2023.

Medical Definition

beta-lactamase

noun
be·​ta-lac·​ta·​mase
variants also β-lactamase
: 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-lactamaseDiana Morgan and Terence Monmaney, Science
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

Note: 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
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