What "bla" Means in Carbapenemase Names
The prefix "bla" stands for beta-lactamase and is the standard nomenclature used to denote genes encoding beta-lactamase enzymes, including carbapenemases 1, 2.
Nomenclature Explanation
The "bla" prefix is universally used in molecular microbiology to identify genes that code for beta-lactamase enzymes. When you see carbapenemase names like:
- blaKPC (Klebsiella pneumoniae carbapenemase)
- blaNDM (New Delhi metallo-beta-lactamase)
- blaOXA-48 (Oxacillinase-48)
- blaVIM (Verona integron-encoded metallo-beta-lactamase)
- blaIMP (Imipenemase)
The "bla" portion simply indicates these are beta-lactamase genes, while the letters/numbers following identify the specific enzyme family 3, 1.
Clinical Context
This nomenclature is critical for:
- Molecular detection methods: PCR assays and whole-genome sequencing specifically target these "bla" genes to identify carbapenemase producers 4, 5
- Epidemiological tracking: Different bla genes indicate different resistance mechanisms and transmission patterns 6
- Treatment decisions: Knowing which specific bla gene is present helps predict susceptibility to newer beta-lactam/beta-lactamase inhibitor combinations 7
Classification by Ambler Class
Carbapenemases with the "bla" prefix belong to three Ambler molecular classes 3, 1:
- Class A (serine-based): blaKPC, blaGES, blaSME, blaIMI
- Class B (metallo-beta-lactamases): blaNDM, blaVIM, blaIMP
- Class D (serine-based): blaOXA-48, blaOXA-23, blaOXA-72
The "bla" prefix itself carries no information about the enzyme's hydrolytic mechanism or substrate profile—it simply identifies the gene as encoding a beta-lactamase enzyme 2.