Memórias do Instituto Oswaldo Cruz
Print version ISSN 0074-0276
SOUZA, Mario RSM et al. Biochemical properties, enterohaemolysin production and plasmid carriage of Shiga toxin-producing Escherichia coli strains. Mem. Inst. Oswaldo Cruz [online]. 2010, vol.105, n.3, pp.318-321. ISSN 0074-0276. http://dx.doi.org/10.1590/S0074-02762010000300013.
Thirty-eight strains of Shiga toxin-producing Escherichia coli (STEC) were characterised in terms of biochemical properties, enterohaemolysin production and plasmid carriage. A wide variation in the biochemical properties was observed among the STEC, with 14 distinct biotypes identified. Biotype 1 was the most common, found in 29% of the strains. Enterohaemolysin production was detected in 29% of the strains. Most of the bacterial strains (95%) carried one or more plasmids and considerable heterogeneity in size and combinations was observed. Seven distinct plasmid profiles were identified. The most common profile, characterised by the presence of a single plasmid of ~90 kb, was found in 50% of these strains. These data indicate extensive diversity among STEC strains. No correlation was found among biotype, serotype, enterohaemolysin production and plasmid profile.
Keywords : Escherichia coli; STEC; plasmid profile; enterohaemolysin; biochemical properties.