State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University (Xiang'an), 361102, Xiamen, Fujian, China.
Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
Commun Biol. 2020 May 22;3(1):256. doi: 10.1038/s42003-020-0974-5.
Viral abundance in deep-sea environments is high. However, the biological, ecological and biogeochemical roles of viruses in the deep sea are under debate. In the present study, microcosm incubations of deep-sea bacterioplankton (2,000 m deep) with normal and reduced pressure of viral lysis were conducted in the western Pacific Ocean. We observed a negative effect of viruses on prokaryotic abundance, indicating the top-down control of bacterioplankton by virioplankton in the deep-sea. The decreased bacterial diversity and a different bacterial community structure with diluted viruses indicate that viruses are sustaining a diverse microbial community in deep-sea environments. Network analysis showed that relieving viral pressure decreased the complexity and clustering coefficients but increased the proportion of positive correlations for the potentially active bacterial community, which suggests that viruses impact deep-sea bacterioplankton interactions. Our study provides experimental evidences of the crucial role of viruses in microbial ecology and biogeochemistry in deep-sea ecosystems.
深海环境中的病毒丰度很高。然而，病毒在深海中的生物、生态和生物地球化学作用仍存在争议。本研究在西太平洋对正常压力和减压条件下的深海细菌浮游生物（2000 米深）进行了微宇宙培养。我们观察到病毒对原核生物丰度的负面影响，表明在深海中噬病毒体对细菌浮游生物具有自上而下的控制作用。细菌多样性的减少和稀释病毒时细菌群落结构的不同表明，病毒在维持深海环境中的微生物群落多样性方面发挥了作用。网络分析表明，减轻病毒压力降低了潜在活性细菌群落的复杂性和聚类系数，但增加了正相关的比例，这表明病毒会影响深海细菌浮游生物的相互作用。本研究为病毒在深海生态系统中的微生物生态和生物地球化学中发挥关键作用提供了实验证据。
