Susceptibilidad in vitro a antimicrobianos y producción de ß-lactamasas de Vibrio y Photobacterium marinos

Abstract

Four marine strains of Vibrio and Photobacterium were tested for their susceptibilities to 22 antimicrobial agents. All strains were susceptible to chloramphenicol, nalidixic acid, cotrimoxazole, tetracycline, netilmicin and norfloxacin; all were resistant to penicillin and ampicillin, and exhibited ß-lactamase activity. However, there were significant differences between strains, especially in their patterns of betalactam and aminoglycosides susceptibility. Vibrio splendidus biovar 1 and Vibrio harveyi have ß-lactamases of the 2d group (cloxacillin-hydrolyzing ß-lactamases), Photobacterium angustum has ß-lactamases of the 2b group (broad-spectrum ß-lactamases inhibited by clavulanic acid), and Photobacterium phosphoreum var. K has ß-lactamases of the 2c group (carbenicillin-hydrolyzing ß-lactamases inhibited by clavulanic acid).

Ha sido estudiada la actividad in vitro de 22 antimicrobianos frente a cuatro cepas de Vibrio y Photobacterium de origen marino. Todas las cepas son susceptibles a cloranfenicol, ácido nalidíxico, cotrimoxazol, tetraciclina, netilmicina y norfloxacina; resistentes a penicilina y ampicilina, y producen ß-lactamasas. Sin embargo, hay diferencias significativas entre las cepas, especialmente en sus patrones de sensibilidad a otros antibióticos betalactámicos y aminoglicósidos. Vibrio splendidus biovar 1 y Vibrio harveyi poseen ß-lactamasas pertenecientes al grupo 2d (ß-lactamasas que hidrolizan la cloxacilina); Photobacterium angustum, ß-lactamasas del grupo 2b (ß-lactamasas de amplio espectro inhibidas por el ácido clavulánico); y Photobacterium phosphoreum var. K, ß-lactamasas del grupo 2c (ß-lactamasas que hidrolizan la carbenicilina y son inhibidas por el ácido clavulánico).