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Abstract We report the isolation a halophilic bacterium that degrades both aromatic and aliphatic hydrocarbons as the sole sources of carbon at high salinity from produced water. Phylogenetic analysis of 16S rRNA-gene sequences shows the isolate is a close relative of Modicisalibacter tunisiensis isolated from an oil-field water in Tunisia. We designate our isolate as Modicisalibacter sp. strain Wilcox. Genome analysis of strain Wilcox revealed the presence of a repertoire of genes involved in the metabolism of aliphatic and aromatic hydrocarbons. Laboratory culture studies corroborated the predicted hydrocarbon degradation potential. The strain degraded benzene, toluene, ethylbenzene, and xylenes at salinities ranging from 0.016 to 4.0 M NaCl, with optimal degradation at 1 M NaCl. Also, the strain degraded phenol, benzoate, biphenyl and phenylacetate as the sole sources of carbon at 2.5 M NaCl. Among aliphatic compounds, the strain degraded n-decane and n-hexadecane as the sole sources of carbon at 2.5 M NaCl. Genome analysis also predicted the presence of many heavy metal resistance genes including genes for metal efflux pumps, transport proteins, and enzymatic detoxification. Overall, due to its ability to degrade many hydrocarbons and withstand high salt and heavy metals, strain Wilcox may prove useful for remediation of produced waters.
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Comparative Genomics Analysis of the Aromatic and Xenobiotic Degradation Capacities and Heavy Metal Resistance in Seven Environmentally Derived Bacterial Isolates
This work is a comparative genomics investigation of the aromatic and xenobiotic compound degradation capabilities and heavy metal resistance of environmental bacterial isolates previously identified by our lab, Achromobacter xylosoxidans ADAF13, Exiguobacterium sp. KKBO11, Ochrobactrum anthropi FRAF13, Pseudomonas putida CBF10-2, Pseudomonas stutzeri ODKF13, Rhizobium radiobacter GHKF11, and Stenotrophomonas maltophilia CBF10-1. This work sought to assess the potential of these isolates as bioremediation tools. We found a variety of aromatic degradation pathways though none directly acts on industrial compounds such as polycyclic aromatic compounds, benzene, phthalate, or xylene. Achromobacter xylosoxidans ADAF13, P. putida CBF10-2, and P. stutzeri ODKF13 showed the most complete pathways for aromatic compound degradation and halobenzoate degradation. All isolates contained heavy metal resistance genes for arsenic, cadmium, copper, chromium, lead, mercury, and zinc. Arsenic resistance genes were the most common among isolates and were organized into structurally diverse ars operons. Collectively, our data indicated that A. xylosoxidans ADAF13, P. putida CBF10-2, and P. stutzeri ODKF13 are strong candidates for further enhancement and development as bioremediation tools.
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- PAR ID:
- 10485222
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Water, Air, & Soil Pollution
- Volume:
- 234
- Issue:
- 7
- ISSN:
- 0049-6979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s11270-023-06495-2
