betalactamasestable

betalactamasestable is a descriptor used in microbiology to refer to beta-lactamase enzymes that retain activity under challenging conditions or resist inactivation by inhibitors. It is not a formal taxonomic term, but a concept used to discuss enzyme robustness and resistance persistence.

Beta-lactamases hydrolyze the beta-lactam ring, rendering many penicillins and cephalosporins ineffective. Stability refers to the enzyme's resilience to thermal or pH fluctuations, or to chemical inhibitors such as clavulanic acid, tazobactam, or sulbactam. Highly stable enzymes often have broader substrate spectra (e.g., ESBLs and carbapenemases) and can persist in various environments.

Classification and determinants: Beta-lactamases are grouped into classes A–D by Ambler, with serine-based enzymes (A, C, D) and metallo-beta-lactamases (class B). Structural features and genetic context (plasmid-borne, integrons, transposons) contribute to stability and to the spread of resistance. Examples include common ESBLs (CTX-M, SHV, TEM variants) and carbapenemases (KPC, NDM, OXA-48-like).

Clinical and laboratory relevance: Stable beta-lactamases limit therapeutic options, drive selection for combination therapies, and complicate infection control. Detection relies on phenotypic assays that test susceptibility patterns and inhibition profiles, and molecular assays that identify bla genes. Understanding stability informs surveillance and drug development.