RESUMO
A total of 153 Aeromonas strains were analyzed by multilocus enzyme electrophoresis. All 11 genetic loci were polymorphic with three to 14 alleles per locus (average 6.55). The genetic diversity of each locus varied between 0.095 for indophenol oxidase and 0.881 for the fast variety of malic enzyme. Cluster analysis of the 122 enzyme types revealed a good correlation with taxonomic groupings as determined by DNA-DNA hybridization. In conjunction with biochemical analysis, as few as two enzymes may be sufficient for the identification of all species in the genus Aeromonas.
Assuntos
Aeromonas/enzimologia , Isoenzimas/análise , Aeromonas/classificação , Aeromonas/genética , Aeromonas/isolamento & purificação , Alelos , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , DNA Bacteriano/análise , Eletroforese em Gel de Amido , Variação Genética , Humanos , Isoenzimas/genética , Hibridização de Ácido NucleicoRESUMO
One hundred phenotypic characteristics were determined for 138 clinical and environmental Aeromonas strains. Cluster analysis revealed three major phenons equivalent to the A. hydrophila, A. caviae, and A. sobria groups, each of which contained more than one genospecies and more than one named species. An excellent correlation was found between phenotypic identification and classification based on DNA relatedness. DNA hybridization groups within each of the phenotypic groups were also separable by using a few biochemical characteristics. Key tests were production of acid from or growth on D-sorbitol (which separated DNA hybridization group 3 from groups 1 and 2 within the A. hydrophila phenogroup), growth on citrate (which essentially separated DNA hybridization group 4 from groups 5A and 5B within the A. caviae phenogroup), and growth on DL-lactate (which separated DNA hybridization group 1 from groups 2 and 3 within the A. hydrophila phenogroup as well as group 5A from groups 4 and 5B within the A. caviae phenogroup). All except one strain in the A. sobria phenogroup belonged to DNA hybridization group 8. DNA hybridization groups were not equally distributed among clinical and environmental isolates, suggesting that strains of certain DNA hybridization groups might be less virulent than others.
