Surfactin: a review on novel microbial surfactant

Abstract

Surfactin, being a peptide antibiotic; acts as a pharmacologically and commercially important surfactant to the Gram positive bacteria and endospores. They have been recently purified from the microbial strains as lipopeptides in their secretion. Bacillus spp. is one of the common producers to this biosurfactant. They are synthesized non-ribosomally via large multi-enzymes (non-ribosomal peptide synthetases, NRPSs). The surfactin biosynthetic assembly line (inducible operon) consists of three large NRPSs: SrfA-A (402 kDa), SrfA-B (401 kDa) and SrfA-C (144 kDa), comprising of a total of seven modules. These modules are arranged into core and elongation domains which are responsible for lipopeptide chain formation. Current researchers have studied only about the Bacillus subtilis genome and its molecular biological aspects for surfactin biosynthesis and to some extent in Bacillus licheniformis. Due to structurally homology of the NRPSs synthetase complex and Srf gene, there is a plenty of room at the base to be exploited through the tools of molecular and structural biology with the integration of recombinant DNA technology.