Resumen

ZAMBRANO, J. L.; BOTERO, L.; CAVAZZA, M. E.  y  AVILA, M.. Resistance to antimicrobial agents and plasmids presence in Escherichia coli strains from raw and treated waters of the stabilization pounds for reuse in agriculture.. Rev. Soc. Ven. Microbiol. [online]. 2002, vol.22, n.1, pp.44-50. ISSN 1315-2556.

Abstract It was determined resistance to antibiotics and plasmids presence, in E. coli strains from raw and treated waters, of the stabilization pounds at the university city of The University of Zulia. The resistance determination of the following antibiotics: nalidixic acid (Na), ampicillin (A), amikacin (Ak), chloramphenicol (C), carbenicillin (Cb), trimethoprim (Tr), tobramycin (Tb), tetracycline (T), gentamicin (G) and kanamycin (K), was performed by Kirby-Bauer´s method. The plasmids extraction was performed by Biboin and Doile´s alkaline lisis method. 81,25% of the strain isolated from the untreated wastewater were resistant to A, 68,75% to T, 46,87% to Cb, 12,50% to Tr and 3,12% to C and T. 83,87% of the strains from the treated wastewater were resistant to A, 16,12% to Tr and T, 12,9% to Cb and 3,22% to Ak, C and Tb. 100% of the analyzed strains went sensitive to: Na, G and K. The resistance order determined in the untreated waswater was: A > T b > Tr > Cb > Ak = C = Tb and in the treated wastewater samples: A > T > Cb > Tr > C = Tb. 16.12% and 34.2% of the strains of the raw residual samples and treated respectively presented resistance at last for three antibiotics. The plasmids presence was detected in 87.10% of the selected strains of the raw samples and in 90,62% of the treated waters. The strains of E. coli isolated from treated wastewater presented plasmids and resistance at 7 out of 10 antibiotics, what suggests the genetic exchange between the strains and their potential as pathogens, by combining different properties that contribute to their survival.

Palabras clave : Resistencia a antibióticos; plásmidos; agua residual; lagunas de estabilización; Escherichia coli.