title: Vibrio cholerae phosphatases required for the utilization of nucleotides and extracellular DNA as phosphate sources.
abstract: Phosphate is essential for life, being used in many core processes such as signal transduction and synthesis of nucleic acids. The waterborne agent of cholera, Vibrio cholerae, encounters phosphate limitation in both the aquatic environment and human intestinal tract. This bacterium can utilize extracellular DNA (eDNA) as a phosphate source, a phenotype dependent on secreted endo- and exonucleases. However, no transporter of nucleotides has been identified in V. cholerae, suggesting that in order for the organism to utilize the DNA as a phosphate source, it must first separate the phosphate and nucleoside groups before transporting phosphate into the cell. In this study, we investigated the factors required for assimilation of phosphate from eDNA. We identified PhoX, and the previously unknown proteins UshA and CpdB as the major phosphatases that allow phosphate acquisition from eDNA and nucleotides. We demonstrated separable but partially overlapping roles for the three phosphatases and showed that the activity of PhoX and CpdB is induced by phosphate limitation. Thus, this study provides mechanistic insight into how V. cholerae can acquire phosphate from extracellular DNA, which is likely to be an important phosphate source in the environment and during infection.
authors.affiliation: Howard Hughes Medical Institute and Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA.
authors.forename: EmilyKate
authors.initials: E
authors.lastname: McDonough
authors.affiliation: Howard Hughes Medical Institute and Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Kamp
authors.affiliation: Howard Hughes Medical Institute and Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, 02111, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Camilli
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002771:Cholera / Q000378:metabolism / Q000382:microbiology*; D004247:DNA / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D009711:Nucleotides / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D014734:Vibrio cholerae / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D009711:Nucleotides; D010710:Phosphates; D004247:DNA; D010744:Phosphoric Monoester Hydrolases