title: Arhodomonas sp. strain Seminole and its genetic potential to degrade aromatic compounds under high-salinity conditions.
abstract: Arhodomonas sp. strain Seminole was isolated from a crude oil-impacted brine soil and shown to degrade benzene, toluene, phenol, 4-hydroxybenzoic acid (4-HBA), protocatechuic acid (PCA), and phenylacetic acid (PAA) as the sole sources of carbon at high salinity. Seminole is a member of the genus Arhodomonas in the class Gammaproteobacteria, sharing 96% 16S rRNA gene sequence similarity with Arhodomonas aquaeolei HA-1. Analysis of the genome predicted a number of catabolic genes for the metabolism of benzene, toluene, 4-HBA, and PAA. The predicted pathways were corroborated by identification of enzymes present in the cytosolic proteomes of cells grown on aromatic compounds using liquid chromatography-mass spectrometry. Genome analysis predicted a cluster of 19 genes necessary for the breakdown of benzene or toluene to acetyl coenzyme A (acetyl-CoA) and pyruvate. Of these, 12 enzymes were identified in the proteome of toluene-grown cells compared to lactate-grown cells. Genomic analysis predicted 11 genes required for 4-HBA degradation to form the tricarboxylic acid (TCA) cycle intermediates. Of these, proteomic analysis of 4-HBA-grown cells identified 6 key enzymes involved in the 4-HBA degradation pathway. Similarly, 15 genes needed for the degradation of PAA to the TCA cycle intermediates were predicted. Of these, 9 enzymes of the PAA degradation pathway were identified only in PAA-grown cells and not in lactate-grown cells. Overall, we were able to reconstruct catabolic steps for the breakdown of a variety of aromatic compounds in an extreme halophile, strain Seminole. Such knowledge is important for understanding the role of Arhodomonas spp. in the natural attenuation of hydrocarbon-impacted hypersaline environments.
authors.affiliation: Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA.
authors.forename: Sonal
authors.initials: S
authors.lastname: Dalvi
authors.affiliation: Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA.
authors.forename: Carla
authors.initials: C
authors.lastname: Nicholson
authors.affiliation: Stephenson Research and Technology Center, University of Oklahoma, Norman, Oklahoma, USA.
authors.forename: Fares
authors.initials: F
authors.lastname: Najar
authors.affiliation: Stephenson Research and Technology Center, University of Oklahoma, Norman, Oklahoma, USA.
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Roe
authors.affiliation: Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, Oklahoma, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Canaan
authors.affiliation: Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, Oklahoma, USA.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Hartson
authors.affiliation: Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA babu.fathepure@okstate.edu.
authors.forename: Babu Z
authors.initials: BZ
authors.lastname: Fathepure
mesh_terms: D002853:Chromatography, Liquid; D016000:Cluster Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D042001:Ectothiorhodospiraceae / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D016680:Genome, Bacterial; D006841:Hydrocarbons, Aromatic / Q000378:metabolism*; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D020543:Proteome / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D054712:Salinity; D017422:Sequence Analysis, DNA
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D006841:Hydrocarbons, Aromatic; D020543:Proteome; D012336:RNA, Ribosomal, 16S