RT Journal Article SR Electronic(1) A1 Ye, Jing Jing A1 Reizer, Jonathan A1 Saier, Milton H.YR 1994 T1 Regulation of 2-deoxyglucose phosphate accumulation in Lactococcus lactisvesicles by metabolite-activated, ATP-dependent phosphorylation of serine-46 in HPr of the phosphotransferase system JF Microbiology, VO 140 IS 12 SP 3421 OP 3429 DO https://doi.org/10.1099/13500872-140-12-3421 PB Microbiology Society, SN 1465-2080, AB Lactococcus lactistakes up glucose and the nonmetabolizable glucose analogue 2-deoxyglucose (2DG) via the phosphotransferase system and extrudes the accumulated sugar phosphates in a process apparently dependent on a cytoplasmic sugar-phosphate phosphatase. Uptake of 2DG into L. lactisvesicles was shown to be dependent on an energy source, effectively provided by intravesicular phosphoenolpyruvate (PEP). 2DG phosphate (2DG-P) accumulation in these vesicles was not inhibited, and preaccumulated 2DG-P was not released from them, upon electroporation of fructose 1,6-diphosphate (FDP), gluconate 6-phosphate or 2-phosphoglycerate into the vesicles. Intravesicular but not extravesicular wild-type HPr of Bacillus subtilisalone stimulated uptake, but in the presence of any one of these metabolites, it prevented accumulation of 2DG-P. Intravesicular H15A mutant HPr inhibited uptake and allowed further inhibition of 2DG-P accumulation in the presence of the intravesicular metabolites. Intravesicular S46A mutant HPr stimulated uptake but could not promote inhibition in the presence of the phosphorylated metabolites. The S46D mutant HPr protein promoted regulation, even in the absence of a metabolite. The V maxbut not the K mvalue for 2DG uptake was affected. Accumulation of the natural, metabolizable substrates of the lactose, glucose, mannose and ribose permeases was inhibited by wild-type HPr in the presence of FDP or by S46D mutant HPr. The results establish that HPr serine phosphorylation by the ATP-dependent, metabolite-activated HPr kinase selectively determines the levels of sugar accumulation via the glucose and lactose permeases in L. lactis.They suggest that two primary functions of HPr(Ser) phosphorylation are: (1) to feedback-inhibit the activities of carbohydrate permeases and not merely to create a hierarchy of preferred carbon sources, and (2) to regulate the cytoplasmic concentrations of carbohydrate inducers by exclusion and expulsion mechanisms., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/13500872-140-12-3421