Phosphoglycerate Kinase Is Involved in Carbohydrate Utilization, Extracellular Polysaccharide Biosynthesis, and Cell Motility of pv. Independent of Clp.

Phosphoglycerate kinase (Pgk), catalyzing the reversible conversions between glycerate-1.3-2P and glycerate-3P, plays an important role in carbohydrate metabolism. Here, we show that a Pgk-deficient mutant (NΔ) of pv. () could grow in medium with glucose, galactose, fructose, mannose, or sucrose, as the sole carbon source, suggesting that may employ Entner-Doudoroff (ED) and pentose phosphate pathway (PPP), but not glycolysis, to catabolize glucose. NΔ could not utilize pyruvate, suggesting that Pgk might be essential for gluconeogenesis. Mutation in led to a reduction of extracellular polysaccharide (EPS) biosynthesis, cell motility, and intracellular ATP. As a result, the virulence of NΔ was significantly compromised in soybean. NΔ could be fully complemented by the wild-type , but not by (encoding Crp-like protein). qRT-PCR analyses demonstrated that is regulated by the HrpG/HrpX cascade, but not by Clp. These results suggest that Pgk is involved in carbohydrate utilization, EPS biosynthesis, and cell motility of independent of Clp.