Inhibitory activity of colicin crude exract against different isolates of Enterobac planktonic and biofilm state-teriacea in both

الملخص EN

Colicins are antibacterial proteins produced by bacteria, which can kill bacterial strains closely related to a produced species, in order to reduce environmental competitors for acquiring nutrients and living space.

In vitro experiment was carried out on the antibacterial activity of colicin crude extract against different isolates (E.coli,Klebsiella pneumoniea,Proteus mirabilis and Salmonella typhi) using well assay method for planktonoc cells.

Biofilm killing assay was also used against biofilm embedded cells by using microtiter plate.

The results showed that colicin extract was active against these isolates when found as planktonic and biofilm state.The higher effect of colicin crude extract was observed against E.coli and S.typhi biofilm in compare with other isolates and there was significant effect of colicin extract against all isolates.