Genomic and Proteomic Evidences for Exopolysaccharide Biosynthesis in Sphingobium chungbukense DJ77

Sphingobium chungbukense DJ77 is a Gram-negative bacterium has metabolic capability of producing exopolysaccharide (EPS) as a potential reducing and stabilizing agent for metallic nanoparticle synthesis. In this study, we investigated the genomic and proteomic analysis to verify metabolic pathway and involved genes and enzymes related to EPS biosynthesis in S. chungbukense DJ77. End-sequencing results of randomly selected fosmid library, which were prepared from high molecular weight DNA of S. chungbukense DJ77, showed identity to sequences from genes related the EPS biosynthesis pathways in several bacteria. We also observed that proteomic responses in S. chungbukense DJ77 by heterogeneously expressing gelA and gelN involved in gellan biosynthesis in Sphingomonas elodea. Comparative two-dimensional gel electrophoresis revealed that both GelA and GelN altered internal expression levels of proteins involved in EPS biosynthesis in S. chungbukense DJ77. The results might provide the genomic and proteomic evidences for presence of EPS biosynthesis pathways in S. chungbukense DJ77.