Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.7.1.4 (nitrite reductase)
 1,847 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neisseria meningitidis is a leading bacterial cause of sepsis and meningitis globally with dynamic strain distribution over time. Beginning with an epidemic among Hajj pilgrims in 2000, serogroup W (W) sequence type (ST) 11 emerged as a leading cause of epidemic meningitis in the African 'meningitis belt' and endemic cases in South America, Europe, Middle East and China. Previous genotyping studies were unable to reliably discriminate sporadic W ST-11 strains in circulation since 1970 from the Hajj outbreak strain (Hajj clone). It is also unclear what proportion of more recent W ST-11 disease clusters are caused by direct descendants of the Hajj clone. Whole genome sequences of 270 meningococcal strains isolated from patients with invasive meningococcal disease globally from 1970 to 2013 were compared using whole genome phylogenetic and major antigen-encoding gene sequence analyses. We found that all W ST-11 strains were descendants of an ancestral strain that had undergone unique capsular switching events. The Hajj clone and its descendants were distinct from other W ST-11 strains in that they shared a common antigen gene profile and had undergone recombination involving virulence genes encoding factor H binding protein, nitric oxide reductase, and nitrite reductase. These data demonstrate that recent acquisition of a distinct antigen-encoding gene profile and variations in meningococcal virulence genes was associated with the emergence of the Hajj clone. Importantly, W ST-11 strains unrelated to the Hajj outbreak contribute a significant proportion of W ST-11 cases globally. This study helps illuminate genomic factors associated with meningococcal strain emergence and evolution.
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PMID:Genomic Epidemiology of Hypervirulent Serogroup W, ST-11 Neisseria meningitidis. 2662 15

Meningococci spread via respiratory droplets, whereas the closely related gonococci are transmitted sexually. Several outbreaks of invasive meningococcal disease have been reported in Europe and the United States among men who have sex with men (MSM). We recently identified an outbreak of serogroup C meningococcal disease among MSM in Germany and France. In this study, genomic and proteomic techniques were used to analyze the outbreak isolates. In addition, genetically identical urethritis isolates were recovered from France and Germany and included in the analysis. Genome sequencing revealed that the isolates from the outbreak among MSM and from urethritis cases belonged to a clade within clonal complex 11. Proteome analysis showed they expressed nitrite reductase, enabling anaerobic growth as previously described for gonococci. Invasive isolates from MSM, but not urethritis isolates, further expressed functional human factor H binding protein associated with enhanced survival in a newly developed transgenic mouse model expressing human factor H, a complement regulatory protein. In conclusion, our data suggest that urethritis and outbreak isolates followed a joint adaptation route including adaption to the urogenital tract.
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PMID:Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men. 2716 67

Neisseria meningitidis, typically a resident of the oro- or nasopharynx and the causative agent of meningococcal meningitis and meningococcemia, is capable of invading and colonizing the urogenital tract. This can result in urethritis, akin to the syndrome caused by its sister species, N. gonorrhoeae, the etiologic agent of gonorrhea. Recently, meningococcal strains associated with outbreaks of urethritis were reported to share genetic characteristics with the gonococcus, raising the question of the extent to which these strains contain features that promote adaptation to the genitourinary niche, making them gonococcus-like and distinguishing them from other N. meningitidis strains. Here, we analyzed the genomes of 39 diverse N. meningitidis isolates associated with urethritis, collected independently over a decade and across three continents. In particular, we characterized the diversity of the nitrite reductase gene (aniA), the factor H-binding protein gene (fHbp), and the capsule biosynthetic locus, all of which are loci previously suggested to be associated with urogenital colonization. We observed notable diversity, including frameshift variants, in aniA and fHbp and the presence of intact, disrupted, and absent capsule biosynthetic genes, indicating that urogenital colonization and urethritis caused by N. meningitidis are possible across a range of meningococcal genotypes. Previously identified allelic patterns in urethritis-associated N. meningitidis strains may reflect genetic diversity in the underlying meningococcal population rather than novel adaptation to the urogenital tract.
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PMID:Genomic Characterization of Urethritis-Associated Neisseria meningitidis Shows that a Wide Range of N. meningitidis Strains Can Cause Urethritis. 2890 87