Burkholderia cepacia 383
   
   
 

Photo credit: Marc Taylor, Cardiff University, Wales, UK
The Burkholderia cepacia complex (Bcc) comprises at least nine closely related species which can be correctly identified only by polyphasic taxonomic approaches. Members of the complex are among the most metabolically versatile microorganisms known, growing on more than 200 organic compounds, fix N2 and carrying multiple antibiotic resistances. They are involved in important processes such as biodegradation of pollutants, biocontrol of root diseases but some also cause disease in plants, animals and humans. Bcc strains are isolated from very different habitats, including soil, rhizospheres, streams and infected plants, animals and human tissues, especially lungs of Cystic Fibrosis patients (Coenye et. al, 2003). Bcc strains have large and plastic genomes comprised of multiple (2 to 4) replicons, which is thought to give them their ecological versatility. The rather unique genome structural features together with the broad ecological range make this group an interesting model for comparative genomic studies. Such studies can hopefully provide insight into how closely related members of a bacterial group are successful in so many very different environments.

Strain ATCC 17660 (R-18194) was isolated in 1958 from a forest soil in Trinidad and was one the original strains in the famous Stanier et.al, (1966) study of pseudomonads where it was described as Pseudomonas multivorans. Previous pulse field gel electrophoresis experiments suggested that ATCC17760 has an atypical small genome size (4.7 Mb in 2 replicons) hence, comparative analysis with other sequenced Bcc genomes would help to understand genome expansion and test the core gene hypothesis for the Bcc group. However, genome sequencing and new pulse field studies now suggests that ATCC 17760 has an 8.5 Mb genome in 3 replicons. ATCC 17760 was also selected because it is in the same phylogenetic cluster as the B. cepacia type strain, an onion pathogen, and the clinical strain J2315, a devastating pathogen in Cystic Fibrosis patients and sequenced by the Sanger Center. Comparative genomic analysis between the later two may help identify genetic determinants that differentiate clinical from environmental isolates. Information as of 2004 suggests that this strain is not a member of any of the nine Bcc species, and is probably a new species, but among the described species, it appears most closely related to B. cepacia.

Strain equivalencies: ATCC 17760 = LMG 6991 = NCIB 9086 = Stanier strain 383.


References:

Coenye, T. and P. Vandamme. 2003. Diversity and significance of Burkholderia. Environ. Microbiol. (2003) 5(9), 719-29.

Staner, R.Y., N.J. Palleroni, and M Doudoroff. 1966. The aerobic pseudomonads. J. Gen. Microbiol. 43: 159-271.