Cross species signal transfer mediated induction of antibiotic production by the marine bacteria against common bacterial pathogens was investigated in the present study. Marine bacteria were isolated and analyzed for their efficacy in antibiotic production against common clinical pathogens viz., Pseudomonas sp., Escherichia coli, Bacillus subtilis and Proteus sp. Out of 36 bacterial isolates analyzed, four isolates exhibited significant antibacterial activity against Pseudomonas, Bacillus, Proteus, Klebsiella and Escherichia coli Isolate designated as CW 602 produced antibiotic when co-cultured with Pseudomonas and CW 401 produced antibiotic when co-cultured with Bacillus cells. Cell free extract of CW 602 and CW 401 cultivated in the presence of heat killed Pseudomonas, Bacillus cells was subjected to solvent extraction by ethyl acetate and antimicrobial activity was tested by disc diffusion method. Present study on induced antibiotic production by Pseudomonas, Bacillus in bacteria CW 602 and CW 401 pave the way for the discovery of pathogen targeted/ specific antibiotic production
