The role of the tyrosine kinase Wzc (Sll0923) and the phosphatase Wzb (Slr0328) in the production of extracellular polymeric substances (EPS) by Synechocystis PCC 6803.

摘要: Many cyanobacteria produce extracellular polymeric substances (EPS) mainly composed of heteropolysaccharides with unique characteristics that make them suitable for biotechnological applications. However, manipulation/optimization EPS biosynthesis/characteristics is hindered by a poor understanding the production pathways and differences between bacterial species. In this work, genes putatively related to different cyanobacterial polymerization, assembly, export were targeted deletion or truncation in unicellular Synechocystis sp. PCC 6803. No evident phenotypic changes observed some mutants occurring multiple copies genome, namely ∆wzy (∆sll0737), ∆wzx (∆sll5049), ∆kpsM (∆slr2107), ∆kpsM∆wzy (∆slr2107∆sll0737), strongly suggesting functional redundancy. contrast, Δwzc (Δsll0923) Δwzb (Δslr0328) influenced both amount composition EPS, establishing Wzc participates capsular (CPS) released (RPS) polysaccharides, Wzb affects RPS production. The structure was solved (2.28 A), revealing structural relative other phosphatases involved substrate recognition mechanism. addition, showed ATPase autokinase activities typical tyrosine kinases. Most importantly, able dephosphorylate vitro, phosphorylation/dephosphorylation plays role