title: Comparative characterization of the cephamycinase blaCMY-1 gene and its relationship with other beta-lactamase genes.
abstract: A plasmidic beta-lactamase which hydrolyzed cephamycins was first detected and reported in 1989. At that time its description was restricted to phenotypic characteristics. We analyzed nucleotide sequence of its gene and explored it genetic relationship with other bla genes. The deduced amino acid sequence of the blaCMY-1 product was compared with those of other known plasmidic cephamycinases and of chromosomal AmpC beta-lactamases. The results indicate that the relationship of CMY-1 is closest to MOX-1 among the plasmidic cephamycinases and to AmpC of Pseudomonas aeruginosa among the chromosomal cephalosporinases. We conclude that the plasmidic cephamycinases described up to now may be classified into three families, as follows: CMY-1, MOX-1, and FOX-1 with AmpC of P. aeruginosa; CMY-2, BIL-1 and LAT-1 with AmpC of Citrobacter freundii; and MIR-1 with AmpC of Enterobacter cloacae. Plasmidic cephamycinases are now recognized as clinically relevant class C beta-lactamases.
authors.affiliation: Max von Pettenkofer-Institut, München, Federal Republic of Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bauernfeind
authors.forename: I
authors.initials: I
authors.lastname: Stemplinger
authors.forename: R
authors.initials: R
authors.lastname: Jungwirth
authors.forename: R
authors.initials: R
authors.lastname: Wilhelm
authors.forename: Y
authors.initials: Y
authors.lastname: Chong
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D018550:Cephalosporin Resistance; D002513:Cephamycins / Q000378:metabolism / Q000494:pharmacology; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D007526:Isoelectric Point; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010641:Phenotype; D011815:R Factors; D016415:Sequence Alignment; D014169:Transformation, Bacterial; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics*
chemical_list: D002513:Cephamycins; C102789:cephamycinase bla(CMY-1); D001618:beta-Lactamases