Intergenus Protoplast Fusion Studies between Marine Streptomyces Sp. Ans4 and Escherichia Coli

Objective: To study the intergenus protoplast fusion bioactive marine Streptomyces sp ANS4 with the Escherichia coli for the strain improvement. Methods: Protoplast of both the organisms was prepared by lysozyme treatment and fused using polyethylene glycol (PEG). Fusant colonies were regenerated using regeneration medium where all the regenerated colonies are powdery in consistency. Microscopic, cultural, physiological, enzymatic and antibiotic susceptibility characteristics of one fusant culture and both the parent cultures are studied. Growth curve and bioactive metabolite production by both the parent and fusant cultures was also studied. Results: oval shaped protoplasts of both the parent cultures are clearly seen under the phase contrast microscope. All the colonies developed after protoplast fusion on regeneration medium looked like one of the parent culture Streptomyces sp ANS4. One among the 10 antagonistic colonies selected from the regeneration medium was expressed the characteristics of either or both of the parental cultures and certain new characteristics. The results of growth curve study showed that the fusant culture possess 10 hours reduction in attaining stationary phase compared to parent Streptomyces sp ANS4. The antibiotic activity of fusant culture was also higher than the parent cultures. Conclusion: The intergenus protoplast fusion between the Streptomyces sp ANS4 and the E.coli strain results in the reduction in time for secondary metabolite production and also increase in antimicrobial activity. This suggested that the potential bioactive compounds may be obtained in increased quantity from the fusant culture with lesser fermentation period.