Production of siderophores & effect of iron restriction on the protein profiles of Aeromonas species isolated from water & patients suffering from acute diarrhoeal disease

Among 48 strains of Aeromonas species, 21 isolates from patients suffering from acute diarrhoea and 27 from metropolitan water samples grown under iro n-restricted conditions, 45 strains produced siderophores. Forty one of the 46 strains tested produced siderophores on chrome azurol S (CAS) agar, whi le 43 isolates did so when the culture supernatants of the bacterial isolat es grown in minimal medium were assayed with chrome azurol S assay solution . The whole cell protein profiles of A. hydrophila strains grown under iron restricted conditions expressed new proteins that were not detected in tho se cultured in iron rich conditions. Five high molecular weight proteins ra nging from 70 to 96 kDa were distinctly absent in cultures grown in the pre sence of iron, indicating their role in iron acquisition by the aeromonads.