title: Genetic and biochemical properties of AER-1, a novel carbenicillin-hydrolyzing beta-lactamase from Aeromonas hydrophila.
abstract: A novel carbenicillin-hydrolyzing beta-lactamase has been discovered in a blood isolate of Aeromonas hydrophila. The enzyme resembles plasmid-determined carbenicillinases in substrate profile but differs in isoelectric point (pI 5.9) and molecular weight (22,000) and has been termed AER-1. No evidence for a plasmid location could be obtained in A. hydrophila, but the AER-1 gene and resistance to chloramphenicol, streptomycin, and sulfonamide could be transferred by mobilization with IncP plasmids to Escherichia coli, where the gene cluster inserted at a unique chromosomal site. The linked resistances are similar to those found on multiresistance beta-lactamase transposons, but since insertion of the A. hydrophila gene cluster was site specific and recA+ dependent, the cluster is not a functional transposon.
mesh_terms: D000333:Aeromonas / Q000201:enzymology* / Q000235:genetics; D002228:Carbenicillin / Q000378:metabolism*; D003227:Conjugation, Genetic; D004790:Enzyme Induction; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005798:Genes, Bacterial; D007525:Isoelectric Focusing; D008970:Molecular Weight; D010403:Penicillin Resistance; D010405:Penicillinase / Q000378:metabolism*; D010957:Plasmids; D014161:Transduction, Genetic; D001618:beta-Lactamases / Q000032:analysis / Q000235:genetics
chemical_list: D010405:Penicillinase; D001618:beta-Lactamases; D002228:Carbenicillin