2-phosphoglycerate phosphatase and serine biosynthesis in Veillonella alcalescens.
The constituent enzymes for the phosphorylated and nonphosphorylated serine biosynthetic pathways in Veillonella alcalescens were identified and included phosphoserine phosphatase, 3-phosphoglycerate dehydrogenase, glycerate dehydrogenase, phosphoserine aminotransferase, and serine-pyruvate aminotransferase. Cell extracts of the organism were also found to cause the specific dephosphorylation of 2-phosphoglycerate. The phosphatase was purified 39-fold by manganese chloride precipitation, ammonium sulfate precipitation, and DEAE-cellulose chromatography. Sephadex G-200 gel filtration data established an apparent molecular weight of 50000 for the enzyme. The 2-phosphoglycerate phosphatase had a pH optimum of 5.5 and was distinct from phosphoglyceromutase. Assays conducted with the purified enzyme on a number of other phosphorylated intermediates indicated that the phosphatase was most specific for 2-phosphoglycerate. Glucerate, hydroxypyruvate, and serine inhibited the enzyme, whereas succinate stimulated activity. Veillonella 2-phosphoglycerate phosphatase is the first such enzyme to be described in a prokaryote and is probably involved in glycerate generation for the nonphosphorylated serine biosynthetic pathway.
D002848:Chromatography, DEAE-Cellulose; D005988:Glyceric Acids / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D012694:Serine / Q000096:biosynthesis*; D013379:Substrate Specificity; D014678:Veillonella / Q000378:metabolism*
D005988:Glyceric Acids; D012694:Serine; D010744:Phosphoric Monoester Hydrolases; C022364:phosphoglycerate phosphatase