title: The Gonococcal Transcriptome during Infection of the Lower Genital Tract in Women.
abstract: Gonorrhea is a highly prevalent disease resulting in significant morbidity worldwide, with an estimated 106 cases reported annually. Neisseria gonorrhoeae, the causative agent of gonorrhea, colonizes and infects the human genital tract and often evades host immune mechanisms until successful antibiotic treatment is used. The alarming increase in antibiotic-resistant strains of N. gonorrhoeae, the often asymptomatic nature of this disease in women and the lack of a vaccine directed at crucial virulence determinants have prompted us to perform transcriptome analysis to understand gonococcal gene expression patterns during natural infection. We sequenced RNA extracted from cervico-vaginal lavage samples collected from women recently exposed to infected male partners and determined the complete N. gonorrhoeae transcriptome during infection of the lower genital tract in women. On average, 3.19% of total RNA isolated from female samples aligned to the N. gonorrhoeae NCCP11945 genome and 1750 gonococcal ORFs (65% of all protein-coding genes) were transcribed. High expression in vivo was observed in genes encoding antimicrobial efflux pumps, iron response, phage production, pilin structure, outer membrane structures and hypothetical proteins. A parallel analysis was performed using the same strains grown in vitro in a chemically defined media (CDM). A total of 140 genes were increased in expression during natural infection compared to growth in CDM, and 165 genes were decreased in expression. Large differences were found in gene expression profiles under each condition, particularly with genes involved in DNA and RNA processing, iron, transposase, pilin and lipoproteins. We specifically interrogated genes encoding DNA binding regulators and iron-scavenging proteins, and identified increased expression of several iron-regulated genes, including tbpAB and fbpAB, during infection in women as compared to growth in vitro, suggesting that during infection of the genital tract in women, the gonococcus is exposed to an iron deplete environment. Collectively, we demonstrate that a large portion of the gonococcal genome is expressed and regulated during mucosal infection including genes involved in regulatory functions and iron scavenging.
authors.affiliation: Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, Boston, MA, United States of America; Department of Microbiology, Boston University School of Medicine, Boston, MA, United States of America.
authors.forename: Ryan
authors.initials: R
authors.lastname: McClure
authors.affiliation: Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, Boston, MA, United States of America.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Nudel
authors.affiliation: Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, Boston, MA, United States of America.
authors.forename: Paola
authors.initials: P
authors.lastname: Massari
authors.affiliation: Department of Computer Science, Wellesley College, Wellesley, MA, United States of America.
authors.forename: Brian
authors.initials: B
authors.lastname: Tjaden
authors.affiliation: STD Clinic, Institute of Dermatology, Chinese Academy of Medical Sciences & Peking Union Medical College, Nanjing 210042, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Su
authors.affiliation: Department of Medicine, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States of America.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Rice
authors.affiliation: Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, Boston, MA, United States of America; Department of Microbiology, Boston University School of Medicine, Boston, MA, United States of America.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Genco
mesh_terms: D000328:Adult; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002584:Cervix Uteri / Q000378:metabolism / Q000382:microbiology*; D005260:Female; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D006069:Gonorrhea / Q000175:diagnosis / Q000378:metabolism / Q000382:microbiology*; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D009344:Neisseria gonorrhoeae / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D059467:Transcriptome; D014621:Vagina / Q000378:metabolism / Q000382:microbiology*; D055815:Young Adult
chemical_list: D001426:Bacterial Proteins; D007501:Iron