TY  - JOUR
A1  - Klughammer, Johanna
A1  - Dittrich, Marcus
A1  - Blom, Jochen
A1  - Mitesser, Vera
A1  - Vogel, Ulrich
A1  - Frosch, Matthias
A1  - Goesmann, Alexander
A1  - Müller, Tobias
A1  - Schoen, Christoph
T1  - Comparative genome sequencing reveals within-host genetic changes in Neisseria meningitidis during invasive disease
JF  - PLoS ONE
N2  - Some members of the physiological human microbiome occasionally cause life-threatening disease even in immunocompetent individuals. A prime example of such a commensal pathogen is Neisseria meningitidis, which normally resides in the human nasopharynx but is also a leading cause of sepsis and epidemic meningitis. Using N. meningitidis as model organism, we tested the hypothesis that virulence of commensal pathogens is a consequence of within host evolution and selection of invasive variants due to mutations at contingency genes, a mechanism called phase variation. In line with the hypothesis that phase variation evolved as an adaptation to colonize diverse hosts, computational comparisons of all 27 to date completely sequenced and annotated meningococcal genomes retrieved from public databases showed that contingency genes are indeed enriched for genes involved in host interactions. To assess within-host genetic changes in meningococci, we further used ultra-deep whole-genome sequencing of throat-blood strain pairs isolated from four patients suffering from invasive meningococcal disease. We detected up to three mutations per strain pair, affecting predominantly contingency genes involved in type IV pilus biogenesis. However, there was not a single (set) of mutation(s) that could invariably be found in all four pairs of strains. Phenotypic assays further showed that these genetic changes were generally not associated with increased serum resistance, higher fitness in human blood ex vivo or differences in the interaction with human epithelial and endothelial cells in vitro. In conclusion, we hypothesize that virulence of meningococci results from accidental emergence of invasive variants during carriage and without within host evolution of invasive phenotypes during disease progression in vivo.
KW  - blood
KW  - comparative genomics
KW  - throat
KW  - genetic loci
KW  - Neisseria meningitidis
KW  - genomic libraries
KW  - genome sequencing
KW  - sequence assembly tools
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159547
VL  - 12
IS  - 1
ER  - 
TY  - JOUR
A1  - Taha, Muhamed-Kheir
A1  - Claus, Heike
A1  - Lappann, Martin
A1  - Veyrier, Frédéric J.
A1  - Otto, Andreas
A1  - Becher, Dörte
A1  - Deghmane, Ala-Eddine
A1  - Frosch, Matthias
A1  - Hellenbrand, Wiebke
A1  - Hong, Eva
A1  - du Châtelet, Isabelle Parent
A1  - Prior, Karola
A1  - Harmsen, Dag
A1  - Vogel, Ulrich
T1  - Evolutionary Events Associated with an Outbreak of Meningococcal Disease in Men Who Have Sex with Men
JF  - PLoS ONE
N2  - 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.
KW  - nitrites
KW  - genome sequencing
KW  - men who have sex with men
KW  - meningococcal disease
KW  - Neisseria meningitidis
KW  - Neisseria gonorrhoeae
KW  - mammalian genomics
KW  - mouse models
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-179870
VL  - 11
IS  - 5
ER  -