title: Genomic analysis of the phenylacetyl-CoA pathway in Burkholderia xenovorans LB400.
abstract: The phenylacetyl-CoA (Paa) catabolic pathway and genome-wide gene expression responses to phenylacetate catabolism were studied in the polychlorinated biphenyl (PCB)-degrading strain Burkholderia xenovorans LB400. Microarray and RT-qPCR analyses identified three non-contiguous chromosomal clusters of genes that are predicted to encode a complete Paa pathway that were induced up to 40-fold during growth of LB400 on phenylacetate: paaGHIJKR, paaANEBDF, and paaC. Comparison of the available genome sequences revealed that this organization is unique to Burkholderiaceae. Parallel proteomic studies identified 7 of the 14 predicted Paa proteins, most of which were detected only in phenylacetate-grown cells, but not in benzoate- or succinate-grown cells. Finally, the transcriptomic and proteomic analyses revealed the induction of at least 7 predicted catabolic pathways of aromatic compounds and some aromatic plant products (phenols, mandelate, biphenyl, C(1) compounds, mevalonate, opine, and isoquinoline), as well as an oxidative stress response and a large group of transporters. Most of these genes were not induced during growth on benzoate or biphenyl, suggesting that phenylacetate or a metabolite may act as a signal that triggers multiple physiological processes. Identifying the components of the Paa pathway is important since the pathway appears to contribute to virulence of Burkholderia pathogens.
authors.affiliation: Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada. m.patrauchan@okstate.edu
authors.forename: Marianna A
authors.initials: MA
authors.lastname: Patrauchan
authors.forename: J Jacob
authors.initials: JJ
authors.lastname: Parnell
authors.forename: Michael P
authors.initials: MP
authors.lastname: McLeod
authors.forename: Christine
authors.initials: C
authors.lastname: Florizone
authors.forename: James M
authors.initials: JM
authors.lastname: Tiedje
authors.forename: Lindsay D
authors.initials: LD
authors.lastname: Eltis
mesh_terms: D000105:Acetyl Coenzyme A / Q000378:metabolism*; D019117:Burkholderia / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D015870:Gene Expression; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D018384:Oxidative Stress / Q000235:genetics; D011078:Polychlorinated Biphenyls / Q000378:metabolism; D040901:Proteomics; D059467:Transcriptome
chemical_list: D000105:Acetyl Coenzyme A; C037816:phenylacetyl-coenzyme A; D011078:Polychlorinated Biphenyls