Previous Article | Next Article ![]()
Journal of Clinical Microbiology, 11 1996, 2741-2747, Vol 34, No. 11
S Chatellier, H Huet, S Kenzi, A Rosenau, P Geslin and R Quentin
The genetic diversity of a collection of 54 unrelated Streptococcus
agalactiae strains isolated from the cerebrospinal fluid of neonates and of
60 unrelated carrier strains was evaluated by investigating the restriction
fragment length polymorphism of the rRNA gene region. Three restriction
enzymes were selected for use: PstI, HindIII, and CfoI. Clustering analysis
revealed two phylogenetic groups of strains with 40% divergence. Group I
contained two clusters, A and B, and group II contained three clusters, C,
D, and E. Strains of serotype Ia were mostly distributed in cluster A, and
strains of serotype Ib were mostly distributed in cluster E. Serotype III
isolates did not cluster. Nevertheless, 37 of 39 isolates belonging to
cluster B were serotype III. With HindIII, two rRNA gene banding patterns
characterized 38 of the 39 strains of cluster B, which represents a
high-virulence group. In addition, two rRNA gene banding patterns with each
enzyme and/or a pair of CfoI fragments of 905 and 990 bp identified 81% of
the invasive strains. On account of the genetic homogeneity of the
cerebrospinal fluid strains, ribotyping is a powerful typing method for
investigation of nosocomial or epidemic invasive infections only when all
three enzymes are used or when PstI and HindIII or PstI and CfoI are
combined with serotyping (index of discrimination, > 0.95).
Copyright © 1996 by the American Society for Microbiology. All rights reserved.
Genetic diversity of rRNA operons of unrelated Streptococcus agalactiae strains isolated from cerebrospinal fluid of neonates suffering from meningitis
Departement de Microbiologie Medicale et Moleculaire, Centre National de la Recherche Scientifique, Centre Hospitalier Universitaire Bretonneau, Tours, France.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»