Restriction site polymorphisms in the genes encoding new members of group 3 outer membrane protein family of Brucella spp

FEMS Microbiol Lett. 2005 Apr 1;245(1):79-84. doi: 10.1016/j.femsle.2005.02.026.


Thirty-seven Brucella reference and field strains representing all the species and their biovars were analysed by PCR-RFLP to determine the degree of variation in the genes encoding the new members of group 3 outer membrane protein (Omp) family. Analysis of the omp22 and omp25c/omp25d genes indicated that the restriction patterns were identical for all species and biovars with all restriction enzymes tested, except for Brucella ovis that showed a short 30 bp deletion close to omp22 gene, and for B. abortus biovar 6 and B. ovis that lacked a DdeI site and a HinfI site, respectively, in the omp25c/omp25d genes. Analysis of PCR products of the omp31b gene digested with 20 restriction enzymes revealed that this gene has a greater level of DNA polymorphism than the other genes encoding the new members of group 3 Omp family. A deletion of 232bp was detected in fourteen B melitensis strains from different hosts and from different geographic origins, confirming that this feature is indeed a hallmark of B. melitensis. PCR-RFLP analysis of omp31b with DdeI allowed us to identify species-specific markers for B. abortus, B. melitensis, and B. ovis. Finally, by PCR analysis, Southern blot hybridization and DNA sequencing we showed that a large deletion of 15 kb, comprising the entire omp25b gene and 21 more genes, is present in all B. ovis strains, thus confirming previous observations from other authors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Outer Membrane Proteins / genetics*
  • Bacterial Outer Membrane Proteins / metabolism
  • Brucella / classification*
  • Brucella / genetics
  • Brucella / growth & development
  • Brucella / metabolism
  • Cattle
  • Humans
  • Polymerase Chain Reaction*
  • Polymorphism, Genetic*
  • Polymorphism, Restriction Fragment Length*
  • Sequence Analysis, DNA
  • Species Specificity


  • Bacterial Outer Membrane Proteins