title: Key role of an ADP - ribose - dependent transcriptional regulator of NAD metabolism for fitness and virulence of Pseudomonas aeruginosa.
abstract: NAD is an essential co-factor of redox reactions and metabolic conversions of NAD-dependent enzymes. NAD biosynthesis in the opportunistic pathogen Pseudomonas aeruginosa has yet not been experimentally explored. The in silico search for orthologs in the P. aeruginosa PAO1 genome identified the operon pncA - pncB1-nadE (PA4918-PA4920) to encode the nicotinamidase, nicotinate phosporibosyltransferase and Nad synthase of salvage pathway I. The functional role of the preceding genes PA4917 and PA4916 was resolved by the characterization of recombinant protein. PA4917 turned out to encode the nicotinate mononucleotide adenylyltransferase NadD2 and PA4916 was determined to encode the transcriptional repressor NrtR that binds to an intergenic sequence between nadD2 and pncA. Complex formation between the catalytically inactive Nudix protein NrtR and its DNA binding site was suppressed by the antirepressor ADP-ribose. NrtR plasposon mutagenesis abrogated virulence of P. aeruginosa TBCF10839 in a murine acute airway infection model and constrained its metabolite profile. When grown together with other isogenic plasposon mutants, the nrtR knock-out was most compromised in competitive fitness to persist in nutrient-rich medium in vitro or murine airways in vivo. This example demonstrates how tightly metabolism and virulence can be intertwined by key elements of metabolic control.
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Elza
authors.initials: E
authors.lastname: Okon
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Dethlefsen
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Pelnikevich
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Andrea van
authors.initials: AV
authors.lastname: Barneveld
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Antje
authors.initials: A
authors.lastname: Munder
authors.affiliation: Klinische Forschergruppe, OE 6710, Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany. Electronic address: tuemmler.burkhard@mh-hannover.de.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Tümmler
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D001426:Bacterial Proteins; D003412:Cricetulus; D004195:Disease Models, Animal; D005260:Female; D015964:Gene Expression Regulation, Bacterial; D008809:Mice, Inbred C3H; D009243:NAD / Q000378:metabolism*; D009876:Operon; D011552:Pseudomonas Infections / Q000382:microbiology / Q000473:pathology; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D012141:Respiratory Tract Infections / Q000382:microbiology / Q000473:pathology; D014157:Transcription Factors / Q000378:metabolism*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors; D009243:NAD; D000246:Adenosine Diphosphate Ribose
keywords: Airway infection model; Fitness experiments; Metabolome; NAD biosynthesis; Nudix protein; Pseudomonas aeruginosa