Antagonistic interactions and phylogenetic diversity of antimicrobial agents producing marine bacteria in Suez Bay

Estimation of the total viable bacterial counts and some physicochemical parameters in different sites selected along the Suez Bay was carried out. The highest bacterial density is positively correlated with pollution strength and is localized at the end of the Suez Bay on the one hand of Suez Gulf. It is also function of pollution strength at different examined sites. Antagonistic interactions among the most dominating twenty-two bacterial isolates were assayed. The marine isolate AB12 isolated from sea water of NIOF station displayed the highest antagonistic activity (42.8%). Antagonistic isolates were assigned to phylogenetically 4 different phena which were identified as Staphylococcus, Micrococcus, Enterococcus and Enterobacter species in addition to 5 single clusters which were identified as Acinetobacter sp. and Pseudomonas sp. The promising strain was identified at the molecular level as Pseudoalteromonas piscicida.