A Species-Specific DNA Probe Obtained From Streptococcus Salivarius Subsp. Thermophilus Detects Strain Restriction Polymorphism

FEMS Microbiol Lett. 1991 Jun 15;65(2):123-8. doi: 10.1016/0378-1097(91)90290-q.


Genomic polymorphism in Streptococcus salivarius subsp. thermophilus was revealed by DNA restriction pattern analysis. A 4.2-kb variable DNA fragment was cloned from strain NST7 and hybridised with the DNA of 25 strains allowing an easy detection of intraspecific RFLP. Strong and weak hybridisation signals were observed and the latter were specifically revealed by a 2.1-kb fragment of the probe. Probe specificity was demonstrated by the absence of homology with DNA of strains belonging to 10 other species, with the exception of S. salivarius subsp. salivarius, confirming a close relationship between S. salivarius and S. thermophilus.

MeSH terms

  • Cloning, Molecular
  • DNA Probes
  • DNA Restriction Enzymes
  • DNA, Bacterial / genetics
  • Nucleic Acid Hybridization
  • Polymorphism, Restriction Fragment Length*
  • Streptococcus / genetics*


  • DNA Probes
  • DNA, Bacterial
  • DNA Restriction Enzymes