Characterization of Escherichia coli D7111 producing the β-lactamase TEM-176

• Main Authors: Joaquim Ruiz, Maria J. Pons, Susan Mosquito, Theresa J. Ochoa, Yolanda Sáenz
• Format: Article
• Language: Spanish
• Published: Instituto Nacional de Salud 2021-03-01
• Series: Revista Peruana de Medicina Experimental y Salud Pública
• Subjects: ampicilina; amoxicilina-ácido clavulánico; beta-lactamasas; resistencia a antibióticos; escherichia coli enterotoxigénica; epidemiología molecular; integrones
• Online Access: https://rpmesp.ins.gob.pe/index.php/rpmesp/article/view/6727

The present report is the original description of blaTEM-176. The mechanisms of resistance to antimicrobial agents were determined in an enterotoxigenic Escherichia coli, determining the susceptibility to 22 antimicrobials classified in 15 different groups by agar diffusion and establishing the phylogenetic group, mechanisms of resistance and presence of Class 1 and 2 integrons. Integrons and β-lactam resistance genes were sequenced. The isolate, belonging to phylogenetic group A, showed the presence of resistance or diminished susceptibility to a ampicillin, amoxicillin plus clavulanic acid, nalidíxic acid, ciprofloxacin, streptomycin, kanamycin, tetracycline, trimethoprim, sulfisoxazole, cotrimoxazole, azithromycin and nitrofurantoin, carrying blaTEM, aadA1/2, aphA1, sul3, tet(A) and a Class 2 integron containing a dfrA1 gene. Quinolone resistance was related to the substitution Ser83Ala. The TEM sequencing showed the presence of the new substitution Ala222Val, which led to the description of the new β-lactamase blaTEM-176.