PROSITE documentation PDOC00134 [for PROSITE entry PS00146]

Beta-lactamases classes -A, -C, and -D active site


β-lactamases (EC [1,2] are enzymes which catalyze the hydrolysis of an amide bond in the β-lactam ring of antibiotics belonging to the penicillin/cephalosporin family. Four kinds of β-lactamase have been identified [3]. Class-B enzymes are zinc containing proteins whilst class -A, C and D enzymes are serine hydrolases. The three classes of serine β-lactamases are evolutionary related and belong to a superfamily [4] that also includes DD-peptidases and a variety of other penicillin-binding proteins (PBP's). All these proteins contain a Ser-x-x-Lys motif, where the serine is the active site residue. Although clearly homologous, the sequences of the three classes of serine β-lactamases exhibit a large degree of variability and only a small number of residues are conserved in addition to the catalytic serine.

Since a pattern detecting all serine β-lactamases would also pick up many unrelated sequences, we decided to provide specific patterns, centered on the active site serine, for each of the three classes.

Expert(s) to contact by email:

Brannigan J.

Last update:

April 2006 / Pattern revised.

Technical section

PROSITE methods (with tools and information) covered by this documentation:

BETA_LACTAMASE_A, PS00146; Beta-lactamase class-A active site  (PATTERN)

BETA_LACTAMASE_C, PS00336; Beta-lactamase class-C active site  (PATTERN)

BETA_LACTAMASE_D, PS00337; Beta-lactamase class-D active site  (PATTERN)


1AuthorsAmbler R.P.
TitleThe structure of beta-lactamases.
SourcePhilos. Trans. R. Soc. Lond., B, Biol. Sci. 289:321-331(1980).
PubMed ID6109327

2AuthorsPastor N., Pinero D., Valdes A.M., Soberon X.
TitleMolecular evolution of class A beta-lactamases: phylogeny and patterns of sequence conservation.
SourceMol. Microbiol. 4:1957-1965(1990).
PubMed ID2082152

3AuthorsBush K.
TitleCharacterization of beta-lactamases.
SourceAntimicrob. Agents Chemother. 33:259-263(1989).
PubMed ID2658779

4AuthorsJoris B., Ghuysen J.-M., Dive G., Renard A., Dideberg O., Charlier P., Frere J.M., Kelly J.A., Boyington J.C., Moews P.C.
TitleThe active-site-serine penicillin-recognizing enzymes as members of the Streptomyces R61 DD-peptidase family.
SourceBiochem. J. 250:313-324(1988).
PubMed ID3128280

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