[Resistance to antibiotics and heavy metals from Escherichia coli isolated from sea water and pluvial galeries].
OBJECTIVE
Test the resistance to antibiotics and heavy metals of E. coli strains isolated from storm sewer water and adjacent seawater samples from three beaches (Meio, Area Preta and Ponta Negra) in the city of Natal/RN/Brazil, and determine the association among those characteristics.


METHODS
A total of 98 strains of E. coli, 50 from storm sewers and 48 from the seawater were analyzed resistance to several antimicrobials by disk diffusion and agar dilution and to heavy metals by dilution in plates with aqueous solutions of CuSO4 incorporated to Mueller Hinton agar in concentrations of 100, 150, 200 and 250 ig/mL and HgCl2 in concentrations of 5, 10, 20, 30, and 50 ig/mL. Standard strains were used as control.


RESULTS
Among the twelve antimicrobials tested, 28 (28.5%) of E. coli strains showed resistance to different antimicrobials drugs to seven. The greatest resistance rate was to tetracycline (46.4%), ampicillin (39.3%) and cephalothin (32.1%), with the remainder (nitrophurantoine, nalidixic acid, sulfatomexazol-trimethoprin and chloramphenicol) at lower percentages. Among the heavy metals, all the strains (100%) were resistant to zinc and to copper in the largest concentration (250 ig/mL), and 18.4% were resistant to HgCl the 50 ig/mL. Ten (55.5%) of the E. coli strains resistant to Hg were associated to resistance to antibiotics.


CONCLUSIONS
These results suggest the existence of extra chromosomal genes in E. coli strains isolated from storm sewer water and adjacent seawater, which encoders of the resistance to antibiotics and heavy metals.
Cardonha
Angela Maria Soares
AM
Departamento de Nutrição da Universidade Federal do Rio Grande do Norte.
Vieira
Regine Helena Silva dos Fernandes
RH
Peirano
Gisele
G
Rodrigues
Dália dos Prazeres
Ddos P
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018432:Drug Resistance, Multiple; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D005618:Fresh Water / Q000737:chemistry / Q000382:microbiology*; D019216:Metals, Heavy / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D011891:Rain / Q000737:chemistry / Q000382:microbiology; D012623:Seawater / Q000737:chemistry / Q000382:microbiology*; D012722:Sewage / Q000032:analysis / Q000382:microbiology; D014871:Water Microbiology
D000900:Anti-Bacterial Agents; D019216:Metals, Heavy; D012722:Sewage