Rodgers-Vieira Elyse A, Zhang Zhenfa, Adrion Alden C, Gold Avram, Aitken Michael D
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA.
Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
Appl Environ Microbiol. 2015 Jun;81(11):3775-81. doi: 10.1128/AEM.00033-15. Epub 2015 Mar 27.
Quinones and other oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are toxic and/or genotoxic compounds observed to be cocontaminants at PAH-contaminated sites, but their formation and fate in contaminated environmental systems have not been well studied. Anthracene-9,10-dione (anthraquinone) has been found in most PAH-contaminated soils and sediments that have been analyzed for oxy-PAHs. However, little is known about the biodegradation of oxy-PAHs, and no bacterial isolates have been described that are capable of growing on or degrading anthraquinone. PAH-degrading Mycobacterium spp. are the only organisms that have been investigated to date for metabolism of a PAH quinone, 4,5-pyrenequinone. We utilized DNA-based stable-isotope probing (SIP) with [U-(13)C]anthraquinone to identify bacteria associated with anthraquinone degradation in PAH-contaminated soil from a former manufactured-gas plant site both before and after treatment in a laboratory-scale bioreactor. SIP with [U-(13)C]anthracene was also performed to assess whether bacteria capable of growing on anthracene are the same as those identified to grow on anthraquinone. Organisms closely related to Sphingomonas were the most predominant among the organisms associated with anthraquinone degradation in bioreactor-treated soil, while organisms in the genus Phenylobacterium comprised the majority of anthraquinone degraders in the untreated soil. Bacteria associated with anthracene degradation differed from those responsible for anthraquinone degradation. These results suggest that Sphingomonas and Phenylobacterium species are associated with anthraquinone degradation and that anthracene-degrading organisms may not possess mechanisms to grow on anthraquinone.
醌类和其他含氧多环芳烃（oxy-PAHs）是有毒和/或具有基因毒性的化合物，在多环芳烃污染场地中被视为共污染物，但它们在受污染环境系统中的形成和归宿尚未得到充分研究。在大多数已分析过oxy-PAHs的多环芳烃污染土壤和沉积物中都发现了蒽-9,10-二酮（蒽醌）。然而，关于oxy-PAHs的生物降解知之甚少，也没有描述过能够在蒽醌上生长或降解蒽醌的细菌分离株。降解多环芳烃的分枝杆菌属是迄今为止唯一被研究过代谢多环芳烃醌4,5-芘醌的生物体。我们利用基于DNA的稳定同位素探测（SIP）技术，使用[U-(13)C]蒽醌来鉴定在实验室规模生物反应器处理前后，来自一个前制气厂场地的多环芳烃污染土壤中与蒽醌降解相关的细菌。还进行了[U-(13)C]蒽的SIP实验，以评估能够在蒽上生长的细菌是否与在蒽醌上生长的细菌相同。在生物反应器处理过的土壤中，与蒽醌降解相关的生物体中，与鞘氨醇单胞菌密切相关的生物体最为主要，而在未处理的土壤中，苯基杆菌属的生物体构成了蒽醌降解菌的大多数。与蒽降解相关的细菌与负责蒽醌降解的细菌不同。这些结果表明，鞘氨醇单胞菌属和苯基杆菌属的物种与蒽醌降解有关，并且蒽降解生物体可能不具备在蒽醌上生长的机制。
