title: Dephosphorylation of the Escherichia coli transcriptional antiterminator BglG by the sugar sensor BglF is the reversal of its phosphorylation.
abstract: The Escherichia coli BglF protein catalyzes transport and phosphorylation of beta-glucosides. In addition, BglF is a membrane sensor which reversibly phosphorylates the transcriptional regulator BglG, depending on beta-glucoside availability. Therefore, BglF has three enzymatic activities: beta-glucoside phosphotransferase, BglG phosphorylase, and phospho-BglG (BglG-P) dephosphorylase. Cys-24 of BglF is the active site which delivers the phosphoryl group either to the sugar or to BglG. To characterize the dephosphorylase activity, we asked whether BglG-P can give the phosphoryl group back to Cys-24 of BglF. Here we provide evidence which is consistent with the interpretation that Cys-24-P is an intermediate in the BglG-P dephosphorylation reaction. Hence, the dephosphorylation reaction catalyzed by BglF proceeds via reversal of the phosphorylation reaction.
authors.affiliation: Department of Molecular Biology, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
authors.forename: Q
authors.initials: Q
authors.lastname: Chen
authors.forename: P W
authors.initials: PW
authors.lastname: Postma
authors.forename: O
authors.initials: O
authors.lastname: Amster-Choder
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites; D003545:Cysteine / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008757:Methylglucosides / Q000378:metabolism; D008956:Models, Chemical; D009154:Mutation / Q000235:genetics; D006005:Phosphorylases / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; C079638:BglF protein, E coli; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D008757:Methylglucosides; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; C064872:antiterminator proteins, Bacteria; C027020:methylglucoside; D006005:Phosphorylases; D011494:Protein Kinases; D003545:Cysteine