Physiological and genomic analysis of newly-isolated polysaccharide synthesizing cyanobacterium Chroococcus sp. FPU101 and chemical analysis of the exopolysaccharide

A unicellular cyanobacterium that produces a large amount of exopolysaccharide (EPS) was isolated. The isolate, named Chroococcus sp. FPU101, grew between 20 and 30 degrees C and at light intensities between 10 and 80 mu mol m(-2) s(-1). Purified EPS from Chroococcus sp. FPU101 had a molecular size of 5.9 x 10(3) kDa and contained galactose, rhamnose, fucose, xylose, mannose, glucose, galacturonic acid, and glucuronic acid at a molar ratio of 17.2:15.9:14.1:11.0:9.6:9.5:13.0:9.7. The EPS content significantly increased when the NaCl concentration in the medium was increased from 1.7 to 100 mM. However, high NaCl concentrations did not significantly affect the molecular size or chemical composition of the El'S. The genes wza, wzh, wzc, wzx, wzy, and wzz that are involved in EPS synthesis were conserved in the genome of Chroococcus sp. FPU101, which was sequenced in this study. These results suggest that the Wzy-dependent pathway is potentially involved in EPS production in this organism.

Automated summary

In this study, a unicellular cyanobacterium named Chroococcus sp. FPU101 was isolated, which produces a significant amount of exopolysaccharide (EPS). The research determined the growth conditions and chemical composition of EPS produced by Chroococcus sp. FPU101. Results indicated that an increase in NaCl concentration significantly boosted EPS content in the organism.