International Journal of Current Microbiology and Applied Sciences
Marine Pseudomonas putida; growth optimization; enzyme assay; SDS-PAGE.
Isolation, Characterization and phylogeny of Sponge - associated bacteria with Antimicrobial and Immunomodulatory potential
A.Kalirajan1 , M.Karpakavalli 2 , K.R.Narayanan1 , K.Ambiganandham1 , A.J.A.Ranjitsingh1* and S.Sudhakar3 
1Department of Zoology, Sri Paramakalyani College, Alwarkurichi-627412, M.S.University, Tirunelveli, Tamilnadu, India. 2Department of Pharmaceutical Chemistry, Karpagam College of Pharmacy, Karpagam University, Coimbatore-32, Tamilnadu, India. 3Department of Biotechnology, Manonmaniam Sundaranar University, Alwarkurichi-627412, Tirunelveli, Tamilnadu, India. *Corresponding Author e-mail: 
Sponge associated bacterial strains represent a rich source of bioactive metabolites. The aim of the present investigation was to isolate and characterize bacteria with antimicrobial and immunomodulatory activity from the Indian marine sponge. A total of 10 marine bacterial strains were isolated from the marine sponge Callyspongia dif usa (CSD 1- CSD 10) that was collected from the Gulf of Mannar province, Tuticorin. Of the ten bacterial strains, CSD 5 showed a remarkable antagonistic activity against clinical bacterial pathogens. Based on the Biochemical, morphological and 16 S rRNA the strain CSD 5 was identified as Virgibacillus sp. The bioactive metabolites produced by the strain Virgibacillus sp. was tested for its antimicrobial and immunomodulatory activity. The metabolites produced by the strain Virgibacillus sp. displayed a significant antibacterial activity against several clinical and fish- borne pathogens. Profound antimicrobial activity was found against the clinical strain Pseudomonas aeruginosa and the fish-borne pathogens viz., Plesiomonas shigelloides, Vibririo mimicus and Vibrio alginolyticus and Aeromonas hydrophila The antifungal activity was found to be significant against the pathogenic skin infection causing fungi Tricoderma sp. The immuno stimulative effect of the metabolite on murine model revealed its potential in enhancing both cell mediated and humoral immune response significantly. These findings suggest that the sponge associated bacterial strain Virgibacillus sp. may contribute the search for novel antibiotics to overcome the infections caused by the newly developing multi drug resistant bacterial strains and also for the production of potential immunomodulators. The biopotential of the compound produced by this sponge associated bacterial strain can be bioprospected to produce bioactive compounds with potential antimicrobial and immunostimulating activity which would impact in the production of novel antibiotics and potential immunomodulators in medical microbiology field.  
Sponge- associated bacteria, Phylogeny; Bioactive metabolites; Clinical, Fish-borne pathogens; Antimicrobials; Immuno- modulators.