title: Role for the RecBCD recombination pathway for pilE gene variation in repair-proficient Neisseria gonorrhoeae.
abstract: The role of the RecBCD recombination pathway in PilE antigenic variation in Neisseria gonorrhoeae is contentious and appears to be strain dependent. In this study, N. gonorrhoeae strain MS11 recB mutants were assessed for recombination/repair. MS11 recB mutants were found to be highly susceptible to DNA treatments that caused double-chain breaks and were severely impaired for growth; recB growth suppressor mutants arose at high frequencies. When the recombination/repair capacity of strain MS11 was compared to that of strains FA1090 and P9, innate differences were observed between the strains, with FA1090 and P9 rec(+) bacteria presenting pronounced recombination/repair defects. Consequently, MS11 recB mutants present a more robust phenotype than the other strains that were tested. In addition, MS11 recB mutants are also shown to be defective for pilE/pilS recombination. Moreover, pilE/pilS recombination is shown to proceed with gonococci that carry inverted pilE loci. Consequently, a novel RecBCD-mediated double-chain-break repair model for PilE antigenic variation is proposed.
authors.affiliation: Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115, USA. sahill@niu.edu
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Hill
authors.forename: Tracy
authors.initials: T
authors.lastname: Woodward
authors.forename: Andrew
authors.initials: A
authors.lastname: Reger
authors.forename: Rachel
authors.initials: R
authors.lastname: Baker
authors.forename: Theresa
authors.initials: T
authors.lastname: Dinse
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D043211:Exodeoxyribonuclease V / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D036781:Fimbriae Proteins / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D014644:Genetic Variation / Q000235:genetics*; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000235:genetics* / Q000378:metabolism*; D011995:Recombination, Genetic; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors; C074063:pilE protein, Neisseria gonorrhoeae; C080687:pilS protein, Bacteria; D036781:Fimbriae Proteins; D043211:Exodeoxyribonuclease V