title: A chromosomally integrated bacteriophage in invasive meningococci.
abstract: Cerebrospinal meningitis is a feared disease that can cause the death of a previously healthy individual within hours. Paradoxically, the causative agent, Neisseria meningitidis, is a common inhabitant of the human nasopharynx, and as such, may be considered a normal, commensal organism. Only in a small proportion of colonized people do the bacteria invade the bloodstream, from where they can cross the blood-brain barrier to cause meningitis. Furthermore, most meningococcal disease is caused by bacteria belonging to only a few of the phylogenetic groups among the large number that constitute the population structure of this genetically variable organism. However, the genetic basis for the differences in pathogenic potential remains elusive. By performing whole genome comparisons of a large collection of meningococcal isolates of defined pathogenic potential we brought to light a meningococcal prophage present in disease-causing bacteria. The phage, of the filamentous family, excises from the chromosome and is secreted from the bacteria via the type IV pilin secretin. Therefore, this element, by spreading among the population, may promote the development of new epidemic clones of N. meningitidis that are capable of breaking the normal commensal relationship with humans and causing invasive disease.
authors.affiliation: Institut National de la Santé et de la Recherche Medicale U570, Faculté de Médecine Necker, 75015 Paris, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Bille
authors.forename: Jean-Ralph
authors.initials: JR
authors.lastname: Zahar
authors.forename: Agnes
authors.initials: A
authors.lastname: Perrin
authors.forename: Sandrine
authors.initials: S
authors.lastname: Morelle
authors.forename: Paula
authors.initials: P
authors.lastname: Kriz
authors.forename: Keith A
authors.initials: KA
authors.lastname: Jolley
authors.forename: Martin C J
authors.initials: MC
authors.lastname: Maiden
authors.forename: Catherine
authors.initials: C
authors.lastname: Dervin
authors.forename: Xavier
authors.initials: X
authors.lastname: Nassif
authors.forename: Colin R
authors.initials: CR
authors.lastname: Tinsley
mesh_terms: D001483:Base Sequence; D019295:Computational Biology; D017931:DNA Primers; D036781:Fimbriae Proteins / Q000378:metabolism; D040461:Gene Components; D044404:Genomic Islands / Q000235:genetics*; D023281:Genomics / Q000379:methods; D006801:Humans; D017912:Inovirus / Q000235:genetics* / Q000378:metabolism; D016014:Linear Models; D008585:Meningitis, Meningococcal / Q000382:microbiology*; D008969:Molecular Sequence Data; D009345:Neisseria meningitidis / Q000235:genetics* / Q000472:pathogenicity* / Q000821:virology*; D020411:Oligonucleotide Array Sequence Analysis; D039002:Prophages / Q000235:genetics* / Q000378:metabolism
chemical_list: D017931:DNA Primers; D036781:Fimbriae Proteins