FIG. 4.

Verification of the putative enzyme activities of GgpPS from S. rhizophila DSM 14405, using recombinant proteins obtained after expression of the complete and a truncated ggpPS gene in E. coli. (A) Measurements of enzyme activities with purified complete GgpPS and the truncated GgpS. Enzyme activities were measured in the presence of the precursor UDP-glucose (U) or ADP-glucose (A). (B) Detection of GG-phosphate phosphatase activities after equal amounts of GG-phosphate were incubated with alkaline phosphatase, the purified complete GgpPS, and the purified truncated GgpS. The GG released was detected using gas-liquid chromatography, where 50 μg of sorbitol (Sorbitol) was added as the internal standard.