CAS Key Laboratory of Experimental Marine Biology & Center of Deep Sea Research, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.
Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
mBio. 2022 Aug 30;13(4):e0014322. doi: 10.1128/mbio.00143-22. Epub 2022 Jul 19.
Zero-valent sulfur (ZVS) distributes widely in the deep-sea cold seep, which is an important immediate in the sulfur cycle of cold seep. In our previous work, we described a novel thiosulfate oxidation pathway determined by thiosulfate dehydrogenase (TsdA) and thiosulfohydrolase (SoxB) mediating the conversion of thiosulfate to ZVS in the deep-sea cold seep bacterium Erythrobacter flavus 21-3. However, the occurrence and ecological role of this pathway in the deep-sea cold seep were obscure. Here, we cultured E. flavus 21-3 in the deep-sea cold seep for 10 days and demonstrated its capability of forming ZVS in the field. Based on proteomic, stoichiometric analyses and microscopic observation, we found that this thiosulfate oxidation pathway benefited E. flavus 21-3 to adapt the cold seep conditions. Notably, ~25% metagenomes assembled genomes derived from the shallow sediments of cold seeps contained both and , where presented abundant sulfur metabolism-related genes and active sulfur cycle. Our results suggested that the thiosulfate oxidation pathway determined by TsdA and SoxB existed across many bacteria inhabiting in the cold seep and frequently used by microbes to take part in the active cold seep biogeochemical sulfur cycle. The contribution of microbes to the deep-sea cold seep sulfur cycle has received considerable attention in recent years. In the previous study, we isolated E. flavus 21-3 from deep-sea cold seep sediments and described a novel thiosulfate oxidation pathway in the laboratorial condition. It provided a new clue about the formation of ZVS in the cold seep. However, because of huge differences between laboratory and environment, whether bacteria perform the same thiosulfate oxidation pathway in the deep-sea cold seep should be further confirmed. In this work, we verified that E. flavus 21-3 formed ZVS using this pathway in deep-sea cold seep through cultivation, which confirmed the importance of this thiosulfate oxidation pathway and provided an approach to study the real metabolism of deep-sea microorganisms.
零价硫（ZVS）广泛分布于深海冷泉中，是冷泉硫循环中的重要环节。在我们之前的工作中，通过描述一种新的硫代硫酸盐氧化途径，阐述了由硫代硫酸盐脱氢酶（TsdA）和硫代硫酸盐水解酶（SoxB）介导的深海冷泉中海洋希瓦氏菌 21-3 中硫代硫酸盐向 ZVS 的转化。然而，这种途径在深海冷泉中的发生和生态作用尚不清楚。在这里，我们在深海冷泉中培养海洋希瓦氏菌 21-3 10 天，并在现场证明了其形成 ZVS 的能力。基于蛋白质组学、化学计量分析和显微镜观察，我们发现这种硫代硫酸盐氧化途径使海洋希瓦氏菌 21-3 能够适应冷泉条件。值得注意的是，源自冷泉浅沉积物的宏基因组组装基因组中约有 25%同时包含和 ，其中存在丰富的硫代谢相关基因和活跃的硫循环。我们的研究结果表明，由 TsdA 和 SoxB 决定的硫代硫酸盐氧化途径存在于许多栖息在冷泉中的细菌中，微生物经常利用这种途径参与活跃的冷泉生物地球化学硫循环。近年来，微生物对深海冷泉硫循环的贡献受到了广泛关注。在之前的研究中，我们从深海冷泉沉积物中分离出海洋希瓦氏菌 21-3，并在实验室条件下描述了一种新的硫代硫酸盐氧化途径。这为冷泉中 ZVS 的形成提供了新的线索。然而，由于实验室和环境之间存在巨大差异，细菌是否在深海冷泉中执行相同的硫代硫酸盐氧化途径仍需进一步证实。在这项工作中，我们通过深海冷泉培养验证了海洋希瓦氏菌 21-3 通过该途径形成 ZVS，这证实了该硫代硫酸盐氧化途径的重要性，并为研究深海微生物的真实代谢提供了一种原位方法。
