Sequence analysis of two chromosomally mediated inducible beta-lactamases from Aeromonas sobria, strain 163a, one a class D penicillinase, the other an AmpC cephalosporinase.
Two beta-lactamase genes from Aeromonas sobria, strain 163a, have been cloned and sequenced, one encoding a typical class C cephalosporinase, designated CepS, the other a class D penicillinase, designated AmpS. CepS is predicted to be a mature protein of 38 kDa with a pI value of 7.0. The amino acid sequence of CepS is most similar to that of AmpC from Pseudomonas aeruginosa (54.7%). AmpS is predicted to be a mature protein of 27 kDa with a pI value of 7.9 that mostly closely resembles BLAD from Klebsiella pneumoniae (42.2%), and OXA-1 from Escherichia coli (36.6%), beta-lactamases that are encoded by genes carried on multiresistant transposons. AmpS differs significantly from the other class D beta-lactamases in that it hydrolyses cloxacillin poorly and is inducible. Both genes exhibit a high overall GC content and possess a high NNC and NNG codon preference, similar to that of genes from Pseudomonas spp.
Department of Microbiology and Pathology, School of Medical Sciences, University of Bristol, UK.
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Walsh
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Hall
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MacGowan
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Bennett
D000333:Aeromonas / Q000201:enzymology* / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002510:Cephalosporinase / Q000096:biosynthesis / Q000235:genetics*; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D003470:Culture Media; D004269:DNA, Bacterial / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology; D005798:Genes, Bacterial; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010405:Penicillinase / Q000096:biosynthesis / Q000235:genetics*; D010957:Plasmids
D003470:Culture Media; D004269:DNA, Bacterial; D002510:Cephalosporinase; D010405:Penicillinase