Molecular and biochemical characterization of a novel class A beta-lactamase (HER-1) from Escherichia hermannii.
Escherichia hermannii showed a low level of resistance to amoxicillin and ticarcillin, reversed by clavulanate, and a moderate susceptibility to piperacillin but was susceptible to all cephalosporins. A bla gene was cloned and encoded a typical class A beta-lactamase (HER-1, pI 7.5), which shares 45, 44, 41, and 40% amino acid identity with other beta-lactamases, AER-1 from Aeromonas hydrophila, MAL-1/Cko-1 from Citrobacter koseri, and TEM-1 and LEN-1, respectively. No ampR gene was detected. Only penicillins were efficiently hydrolyzed, and no hydrolysis was observed for cefuroxime and broad-spectrum cephalosporins. Sequencing of the bla gene in 12 other strains showed 98 to 100% identity with bla(HER-1).
Beauchef-Havard
Anne
A
Service de Bactériologie, Hôpital Cochin, AP-HP, Paris, France.
Arlet
Guillaume
G
Gautier
Valerie
V
Labia
Roger
R
Grimont
Patrick
P
Philippon
Alain
A
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004269:DNA, Bacterial / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D004925:Escherichia / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*; D007525:Isoelectric Focusing; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004274:DNA, Recombinant; D001618:beta-Lactamases