EBR-1, a novel Ambler subclass B1 beta-lactamase from Empedobacter brevis.
Empedobacter brevis (formerly designated Flavobacterium breve) is a gram-negative aerobe involved in nosocomial infections. The Ambler class B beta-lactamase gene bla(EBR-1) was cloned and expressed in Escherichia coli from E. brevis clinical strain ASS-1, which had reduced susceptibility to expanded-spectrum cephalosporins and carbapenems. Purified beta-lactamase EBR-1 hydrolyzed penicillins, cephalosporins, and carbapenems efficiently but not aztreonam. Kinetic parameters of EBR-1 were similar to those of class B enzymes such as BlaB, IND-2, and GOB-1 identified from other Flavobacteriaceae species, except for meropenem, which was more hydrolyzed by beta-lactamase GOB-1. EBR-1, with a pI of 8.0 and a relative molecular mass of ca. 25 kDa, was classified in functional subgroup 3a, which includes most of the class B beta-lactamases. EBR-1, which belongs to molecular subclass B1 of metalloenzymes, shares 58, 57, and 42% amino acid identity with the most closely related beta-lactamases, IND-1/IND-2 from Chryseobacterium indologenes, CGB-1 from Chryseobacterium gleum, and BlaB from Chryseobacterium meningosepticum, respectively.
Bellais
Samuel
S
Service de Bactériologie-Virologie, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, 94275 Le Kremlin-Bicêtre Cédex, France.
Girlich
Delphine
D
Karim
Amal
A
Nordmann
Patrice
P
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005417:Flavobacterium / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D047090:beta-Lactams / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases