Burkholderia xenovorans
A Microbial Biorealm page on the genus Burkholderia xenovorans
Classification
Higher order taxa
Bacteria; Proteobacteria; Betaprotobacteria; Burkholderiales; Burkholderiaceae; Burkholderia
Species
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NCBI: Taxonomy |
Genus species
Burkholderia xenovorans
Description and significance
Burkholderia xenovorans is an important aerobic degrader of polychlorinatred biphenyl (PCB), which is an organic chemical that has industrial use but is toxic to animals and humans. The LB400 strain is the most studied strain due to its ability to oxidize over 20 different PCB congeners. It was isolated in a landfill contaminated by PCB in New York over 20 years ago. Burkholderia xenovorans' environmental niche is in soil rhizospheres, which is the soil area surrounding plant roots.
Genome structure
The genome size of Burkholderia xenovorans varies between 7.4 to 9.3 Mbp, depending upon the particular strain. Burkholderia xenovorans has three circular replicons: chromosome 1 at 4.90 Mbp and chromosome 2 at 3.36 Mbp and a megaplasmid at 1.47 Mbp. Chromosome 1 contains homologs of dnaA (a chromosomal replication initiation protein) and dnaN (a DNA polymerase subunit). Chromosome 2 contains genes important for plasmid replication and partitioning, as well as other genes that help Burkholderia xenovorans adapt to it environmental niche. Unlike the chromosomes, the megaplasmid at 1.47 Mbp does not contain any essential functions or RNA.
Cell structure and metabolism
The most interesting feature of Burkholderia xenovorans is its ability to catabolize aromatic compounds, such as those that come out of roots or involved in root turnover. Degradation of aromatic compounds usually involves an initial ring activation through either a hydroxylation by an oxygenase or a CoA ligase-mediated pathway. The aromatic compound then is shunted to one of several different catabolic pathways, depending on the substrate.
Burkholderia xenovorans contains nitrogen fixation genes, which are located on chromosome 2, which can be used to change elemental nitrogen. Burkholderia xenovorans also contains chemotaxis genes which allow it to move toward aromatic compounds in the soil rhizosphere.
Ecology
Burkholderia xenovorans' ability to fix nitrogen make it an important symbiont for plants to thrive in nitrogen-poor soil
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Application to Biotechnology
Does this organism produce any useful compounds or enzymes? What are they and how are they used?
Current Research
Enter summaries of the most recent research here--at least three required
References
Edited by student of Rachel Larsen
