Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China; College of Life Sciences, South China Agricultural University, Guangzhou 510642, China.
Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
J Hazard Mater. 2021 Apr 5;407:124385. doi: 10.1016/j.jhazmat.2020.124385. Epub 2020 Nov 4.
Microbial sulfate-reduction coupling polycyclic aromatic hydrocarbon (PAH) degradation is an important process for the remediation of contaminated sediments. However, little is known about core players and their mechanisms in this process due to the complexity of PAH degradation and the large number of microorganisms involved. Here we analyzed potential core players in a black-odorous sediment using gradient-dilution culturing, isolation and genomic/metagenomic approaches. Along the dilution gradient, microbial PAH degradation and sulfate consumption were not decreased, and even a significant (p = 0.003) increase was observed in the degradation of phenanthrene although the microbial diversity declined. Two species, affiliated with Desulfovibrio and Petrimonas, were commonly present in all of the gradients as keystone taxa and showed as the dominant microorganisms in the single colony (SB8) isolated from the highest dilution culture with 93.49% and 4.73% of the microbial community, respectively. Desulfovibrio sp. SB8 and Petrimonas sp. SB8 could serve together as core players for sulfate-reduction coupling PAH degradation, in which Desulfovibrio sp. SB8 could degrade PAHs to hexahydro-2-naphthoyl through the carboxylation pathway while Petrimonas sp. SB8 might degrade intermediate metabolites of PAHs. This study provides new insights into the microbial sulfate-reduction coupling PAH degradation in black-odorous sediments.
微生物硫酸盐还原耦合多环芳烃（PAH）降解是受污染沉积物修复的一个重要过程。然而，由于 PAH 降解的复杂性和涉及的微生物数量众多，对于该过程中的核心参与者及其机制知之甚少。在这里，我们使用梯度稀释培养、分离和基因组/宏基因组方法分析了黑色恶臭沉积物中的潜在核心参与者。在稀释梯度上，微生物 PAH 降解和硫酸盐消耗并没有减少，尽管微生物多样性下降，但菲的降解甚至显著增加（p=0.003）。两种与脱硫弧菌和 Petrimonas 属相关的微生物作为关键类群普遍存在于所有梯度中，并且是从最高稀释培养物（稀释度为 10-6）中分离出来的单菌落（SB8）中的优势微生物，分别占微生物群落的 93.49%和 4.73%。脱硫弧菌 SB8 和 Petrimonas sp. SB8 可以共同作为硫酸盐还原耦合 PAH 降解的核心参与者，其中脱硫弧菌 SB8 可以通过羧化途径将 PAHs 降解为六氢-2-萘甲酰基，而 Petrimonas sp. SB8 可能降解 PAHs 的中间代谢物。这项研究为黑色恶臭沉积物中微生物硫酸盐还原耦合 PAH 降解提供了新的见解。
