The Journal of Medical Microbiology, Vol 41, Issue 2 112-119, Copyright © 1994 by Society for General Microbiology
A framework for IS200, 16S rRNA gene and plasmid-profile analysis in Salmonella serogroup D1
J. Stanley, N. Powell, C. Jones and A. P. Burnens
NCTC Molecular Genetics Unit, Central Public Health Laboratory.
Chromosomal fingerprinting of the type strains of serotypes of Salmonella
O-serogroup D1 with the DNA insertion sequence IS200 generated patterns
which were either serotype-specific (e.g., Typhi), or conserved among
groups of related serotypes (e.g., Dublin, Rostock and certain phage types
of Enteritidis). The number of IS200 copies varied considerably, and the
IS200 patterns of type strains of serotypes associated with systemic
infections in man were specific and suitable for identifying strains within
those serotypes. Polymorphism at 16S rRNA gene loci was examined among type
strains and 11 16S rRNA gene profiles were characterised. The most
prevalent of these was conserved among type strains of 11 serotypes, and
the next most prevalent among type strains of nine serotypes; together,
they encompassed 15 unique IS200 profiles. The distribution and mol. wts of
plasmids carrying spvBC (virulence) genes could be directly related to
certain chromosomal genotypes defined by IS200 patterns. The presence of
virulence plasmids in serotypes Lomalinda, Antarctica and Wangata is
reported for the first time. Comparison of 16S rRNA gene profiles and IS200
patterns provides a definition of genotype that is applicable to
epidemiological studies of various group D1 serotypes and should prove
particularly useful for those lacking plasmid DNA.
