Characterization of the New AmpC beta-Lactamase FOX-8 Reveals a Single Mutation, Phe313Leu, Located in the R2 Loop That Affects Ceftazidime Hydrolysis
Por:
Perez-Llarena, FJ, Kerff, F, Zamorano, L, Fernandez, MC, Nunez, ML, Miro, E, Oliver, A, Navarro, F, Bou, G
Publicada:
1 oct 2013
Resumen:
A novel class C beta-lactamase (FOX-8) was isolated from a clinical strain of Escherichia coli. The FOX-8 enzyme possessed a unique substitution (Phe313Leu) compared to FOX-3. Isogenic E. coli strains carrying FOX-8 showed an 8-fold reduction in resistance to ceftazidime relative to FOX-3. In a kinetic analysis, FOX-8 displayed a 33-fold reduction in k(cat)/K-m for ceftazidime compared to FOX-3. In the FOX family of beta-lactamases, the Phe313 residue located in the R2 loop affects ceftazidime hydrolysis and alters the phenotype of E. coli strains carrying this variant.
Filiaciones:
Perez-Llarena, FJ:
Complejo Hosp Univ A Coruna, INIBIC, Serv Microbiol, La Coruna, Spain
Kerff, F:
Univ Liege, Ctr Ingn Proteines, Liege, Belgium
Zamorano, L:
Hosp Univ Son Espases, Serv Microbiol, Palma De Mallorca, Spain
Fernandez, MC:
Complejo Hosp Univ A Coruna, INIBIC, Serv Microbiol, La Coruna, Spain
Nunez, ML:
Hosp Gen Univ Reina Soffa, Serv Microbiol, Murcia, Spain
Miro, E:
Univ Autonoma Barcelona, IIB Sant Pau, Hosp Santa Creu Sant Pau, Serv Microbiol, E-08193 Barcelona, Spain
Oliver, A:
Hosp Univ Son Espases, Serv Microbiol, Palma De Mallorca, Spain
Navarro, F:
Univ Autonoma Barcelona, IIB Sant Pau, Hosp Santa Creu Sant Pau, Serv Microbiol, E-08193 Barcelona, Spain
Bou, G:
Complejo Hosp Univ A Coruna, INIBIC, Serv Microbiol, La Coruna, Spain
Green Published, Bronze
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