title: Cloning and characterization of Escherichia coli DUF299: a bifunctional ADP-dependent kinase--Pi-dependent pyrophosphorylase from bacteria.
abstract: BACKGROUND
  Phosphoenolpyruvate synthetase (PEPS; EC 2.7.9.2) catalyzes the synthesis of phosphoenolpyruvate from pyruvate in Escherichia coli when cells are grown on a three carbon source. It also catalyses the anabolic conversion of pyruvate to phosphoenolpyruvate in gluconeogenesis. A bioinformatics search conducted following the successful cloning and expression of maize leaf pyruvate, orthophosphate dikinase regulatory protein (PDRP) revealed the presence of PDRP homologs in more than 300 bacterial species; the PDRP homolog was identified as DUF299.
  
  
  RESULTS
  This paper describes the cloning and expression of both PEPS and DUF299 from E. coli and establishes that E. coli DUF299 catalyzes both the ADP-dependent inactivation and the Pi-dependent activation of PEPS.
  
  
  CONCLUSIONS
  This paper represents the first report of a bifunctional regulatory enzyme catalysing an ADP-dependent phosphorylation and a Pi-dependent pyrophosphorylation reaction in bacteria.
authors.affiliation: Department of Biochemistry and Molecular Biology, James Cook University, Townsville, Queensland 4811, Australia. James.Burnell@jcu.edu.au
authors.forename: Jim N
authors.initials: JN
authors.lastname: Burnell
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D005943:Gluconeogenesis; D009097:Multienzyme Complexes / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010728:Phosphoenolpyruvate / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D017866:Phosphotransferases (Paired Acceptors) / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D011494:Protein Kinases / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D011772:Pyruvate, Orthophosphate Dikinase / Q000145:classification / Q000235:genetics / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism; D003313:Zea mays / Q000201:enzymology
chemical_list: D029968:Escherichia coli Proteins; D009097:Multienzyme Complexes; D000244:Adenosine Diphosphate; D010728:Phosphoenolpyruvate; D019289:Pyruvic Acid; D011494:Protein Kinases; C549142:DUF299 protein, E coli; D017866:Phosphotransferases (Paired Acceptors); D011772:Pyruvate, Orthophosphate Dikinase; C022509:pyruvate, water dikinase; D010744:Phosphoric Monoester Hydrolases