title: Stable polyphosphate accumulation by a pseudo-revertant of an Escherichia coli phoU mutant.
abstract: phoU mutants of bacteria are potentially useful for the removal of inorganic phosphate (Pi) from sewage because they can accumulate a large amounts of polyphosphate (polyP). However, the growth of phoU mutants is severely defective and is easily outgrown by revertant(s) that have lost the ability to accumulate polyP during growth in a nutrient-rich medium. We found that a pseudo-revertant, designated LAP[+], that appeared in a culture of an Escherichia coli phoU mutant that could accumulate polyP even after ten serial passages. Reduction in the expression of the Pi-specific transporter Pst in LAP[+] may contribute to relieving stresses such as excess Pi incorporation that could stimulate reversions. The discovery of a LAP[+] provides a clue to generate phoU mutants that accumulate polyP in a stable manner.
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8530, Japan. hirota@hiroshima-u.ac.jp
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Hirota
authors.forename: Kei
authors.initials: K
authors.lastname: Motomura
authors.forename: Shigeto
authors.initials: S
authors.lastname: Nakai
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Handa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Akio
authors.initials: A
authors.lastname: Kuroda
mesh_terms: D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D033902:Periplasmic Binding Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D028044:Phosphate-Binding Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D011122:Polyphosphates / Q000032:analysis / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D033902:Periplasmic Binding Proteins; D028044:Phosphate-Binding Proteins; D011122:Polyphosphates; C090133:PstS protein, E coli; D012333:RNA, Messenger; D014157:Transcription Factors; C050770:phoU protein, E coli