Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia.
Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, P. O. Box 3665, Abha, 61421, Saudi Arabia.
Arch Microbiol. 2022 Apr 9;204(5):248. doi: 10.1007/s00203-022-02850-9.
Polycyclic aromatic hydrocarbons (PAHs) are the hazardous xenobiotic agents of oil production. One of the methods to eliminate hazardous compounds is bioremediation, which is the most efficient and cost-effective method to eliminate the harmful byproducts of crude petroleum processing. In this study, five pure bacterial isolates were isolated from petroleum-contaminated soil, four of which showed a robust growth on the PAH pyrene, as a sole carbon source. Various methods viz mass spectroscopy, biochemical assays, and 16S RNA sequencing employed to identify the isolates ascertained the consistent identification of Klebsiella oxytoca by all three methods. Scanning electron microscopy and Gram staining further demonstrated the characterization of the K. oxytoca. High-performance liquid chromatography of the culture supernatant of K. oxytoca grown in pyrene containing media showed that the cells started utilizing pyrene from the 6th day onwards and by the 12th day of growth, 70% of the pyrene was completely degraded. A genome search for the genes predicted to be involved in pyrene degradation using Kyoto Encyclopedia of Genes and Genomes (KEGG) confirmed their presence in the genome of K. oxytoca. These results suggest that K. oxytoca would be a suitable candidate for removing soil aromatic hydrocarbons.
多环芳烃（PAHs）是石油生产中的有害异生物质。消除有害化合物的方法之一是生物修复，这是消除原油加工过程中有害副产品最有效和最具成本效益的方法。在这项研究中，从受石油污染的土壤中分离出了五个纯细菌分离株，其中四个在作为唯一碳源的多环芳烃芘上表现出强劲的生长。质谱、生化分析和 16S RNA 测序等各种方法用于鉴定分离株，三种方法均一致鉴定出产酸克雷伯氏菌。扫描电子显微镜和革兰氏染色进一步证明了产酸克雷伯氏菌的特征。在含有芘的培养基中生长的产酸克雷伯氏菌的培养上清液的高效液相色谱分析表明，细胞从第 6 天开始利用芘，到第 12 天生长时，70%的芘已完全降解。使用京都基因与基因组百科全书（KEGG）搜索预测参与芘降解的基因，证实了它们存在于产酸克雷伯氏菌的基因组中。这些结果表明，产酸克雷伯氏菌将是去除土壤芳烃的合适候选者。
