ANTIMICROBIAL ACTIVITY AND CHARACTERIZATION OF MARINE STREPTOMYSIS CHEONANENSIS

Marine environment is a potential source for development of novel natural pharmaceuticals. As marine environmental conditions are different from terrestrial ones, it is surmised that marine actinomycetes might produce novel bioactive compounds. These microbes have characteristics in common to both bacteria and fungi and yet they possess adequate distinctive features to classify them into a separate category. Actinomycetes were cultivated using a variety of media and selective isolation techniques from 15 marine samples collected from the Bay of Bengal. Out of 93 isolates, 11 strains showed high antimicrobial activity against test organisms. The strain AUBT - 902 was selected for further investigation due to its strong antibacterial and antifungal activity and was identified as a member of Streptomyces genus based on its morphological, cultural, physiological, utilization of carbon sources and biochemical characteristics. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain belongs to the genus Streptomyces, with the maximum similarity to Streptomyces cheonanensis (99.6%). On the basis of polyphasic evidence, the strain was recognized as a new isolate of Streptomyces cheonanensis from marine source.