title: Pseudomonas aeruginosa PA1006 is a persulfide-modified protein that is critical for molybdenum homeostasis.
abstract: A companion manuscript revealed that deletion of the Pseudomonas aeruginosa (Pae) PA1006 gene caused pleiotropic defects in metabolism including a loss of all nitrate reductase activities, biofilm maturation, and virulence. Herein, several complementary approaches indicate that PA1006 protein serves as a persulfide-modified protein that is critical for molybdenum homeostasis in Pae. Mutation of a highly conserved Cys22 to Ala or Ser resulted in a loss of PA1006 activity. Yeast-two-hybrid and a green-fluorescent protein fragment complementation assay (GFP-PFCA) in Pae itself revealed that PA1006 interacts with Pae PA3667/CsdA and PA3814/IscS Cys desulfurase enzymes. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) "top-down" analysis of PA1006 purified from Pae revealed that conserved Cys22 is post-translationally modified in vivo in the form a persulfide. Inductively-coupled-plasma (ICP)-MS analysis of ΔPA1006 mutant extracts revealed that the mutant cells contain significantly reduced levels of molybdenum compared to wild-type. GFP-PFCA also revealed that PA1006 interacts with several molybdenum cofactor (MoCo) biosynthesis proteins as well as nitrate reductase maturation factor NarJ and component NarH. These data indicate that a loss of PA1006 protein's persulfide sulfur and a reduced availability of molybdenum contribute to the phenotype of a ΔPA1006 mutant.
authors: Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA. gtombline@urmc.rochester.edu
authors: Gregory
authors: G
authors: Tombline
authors: Johanna M
authors: JM
authors: Schwingel
authors: John D
authors: JD
authors: Lapek
authors: Alan E
authors: AE
authors: Friedman
authors: Thomas
authors: T
authors: Darrah
authors: Michael
authors: M
authors: Maguire
authors: Nadine E
authors: NE
authors: Van Alst
authors: Melanie J
authors: MJ
authors: Filiatrault
authors: Barbara H
authors: BH
authors: Iglewski
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005583:Fourier Analysis; D006706:Homeostasis; D013058:Mass Spectrometry / Q000379:methods; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008982:Molybdenum / Q000378:metabolism*; D016296:Mutagenesis; D050901:Nitrate Reductase / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013440:Sulfides / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D013440:Sulfides; C051552:persulfides; D008982:Molybdenum; D050901:Nitrate Reductase