Effect of stress on production of heat labile enterotoxin by Escherichia coli.
Indian J Med Microbiol
; 27(4): 325-8, 2009.
Article
en En
| MEDLINE
| ID: mdl-19736401
Enterotoxigenic Escherichia coli (ETEC) is an important pathogen responsible for secretory diarrhoea. The production of heat labile enterotoxin (LT), by ETEC, is largely responsible for the pathogenesis of diarrhoea. In the present study we investigated the effect of stress factors such as temperature, pH, osmotic stress and nutritional limitation on the production of LT by ETEC using in-house GMI-ELISA. Four strains of E. coli consisting, one standard strain MTCC 723 and three clinical isolates were used in the study. Maximum amount of LT (OD 3.285) was produced at 37 0 C followed by 40 0 C (OD 3.305). Growth of E. coli in medium with pH 8.6 resulted in maximum amount of LT production (OD 3.489). LT was not detectable when bacteria were grown in medium with pH < or =7.2 and > or = 9.2. Sodium chloride concentration of 0.2 M stimulated maximum amount of LT production. Maximum amount of LT was produced when the bacteria were grown in medium containing 2.5 g/l of glucose. All the stress factors had a significant effect on the LT production by E. coli , though quantitative differences in the various strains were observed.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Estrés Fisiológico
/
Toxinas Bacterianas
/
Proteínas de Escherichia coli
/
Enterotoxinas
/
Escherichia coli Enterotoxigénica
Límite:
Humans
Idioma:
En
Revista:
Indian J Med Microbiol
Asunto de la revista:
MICROBIOLOGIA
Año:
2009
Tipo del documento:
Article
País de afiliación:
India
Pais de publicación:
Estados Unidos