A complex community of microorganisms called the gut microbiota lives in the digestive tracts of humans and animals and varied according to many different factors that shape the whole ecosystem. Bacteriocins are ribosomally synthesized bactericidal peptides that inhibit growth of microorganisms. The presence of bacteriocins throughout microbial populations suggests their importance for bacterial survival in complicated microbial environments. Present study was undertaken to evaluate bacteriocin production from Gram negative bacteria isolated from human faecal samples collected from Baghdad, Iraq. In all, 123 bacterial isolates were obtaineandbe long to families, Enero bacteria ceae and Moraxellaceae. Those were subjected to Cup assay to study bactericidal activity against sensitive E. coli SH-95. On an average, The percentage for bacteriocin production from all isolates was 88%. Among them, Escherichia coli showed highest bacteriocin production (70 %) followed by Klebsiella pneuomniae (10 %) and Citrobacter youngae (7.3%). Acinetobacter baumannii (0.8 %), while Acinetobacter radioresistanse failed to produce bacteriocin. In this study, It was observed that the bacteriocins production from normal flora of healthy individual's gut was greater than that produced by pathological bacteria, since bacteriocins are important for successful gut commensalization in mammals, which harbour a high density and diversity of microbes.
Microbiota, Gram negative, Bacteriocins, Cup Assay
