Burkholderia vietnamiensis G4

Photo credit: Marc Taylor and Louise O'Sullivan, 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.

B. vietnamiensis strain G4 (R1808) is the best trichloroethene (TCE) co-oxidizing strain yet discovered (Fries et.al,, 1997). TCE and its sister chloroethenes are the most widespread hazardous environmental contaminants in groundwaters. Strain G-4 when grown on toluene or phenol produces an oxygenase that degrades TCE. This strain has been used in at a number of polluted sites to aid clean-up of ground water. Strain G-4 was isolated for its TCE oxidizing ability from an industrial waste treatment facility at Pensacola Naval Air Station, Florida (Nelson et. al., 1987). It has also been shown to be rhizosphere competent. Its genome size is estimated to be 8.5Mb. The B. vietnamiensis species is known for its rhizosphere colonizing ability, including on rice, and its ability to fix N2 gas. It is the third most frequent Bcc species isolated from Cystic Fibrosis patients. Besides its pollutant degrading ability, this strain was sequenced because well-characterized members of this species come from the CF lung, rice rhizosphere and soil, and hence offer the prospect for differentiating traits important to each habitat.

Strain equivalencies ATCC 53617 = G-4


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

Fries, M.R., L.J. Forney, and J.M. Tiedje. 1997. Phenol- and toluene-degrading microbial populations from an aquifer in which successful trichloroethene cometabolism occurred. Appl. Environ. Microbiol. 63:1523-1530.

Nelson MJ, S.O. Montgomery, W.R. Mahaffey, P.H. Pritchard. 1987. Biodegradation of trichloroethylene and involvement of an aromatic biodegradative pathway. Appl Environ Microbiol. 53:949-54.