红树林湿地硫酸盐还原菌的多样性及其参与驱动的元素耦合机制

Sulfate-reducing prokaryotes in mangrove wetlands: diversity and role in driving element coupling

摘要:

红树林生态系统是热带和亚热带地区重要的滨海湿地，具有营养物质形态多样化和高效动态变化的特征，是驱动碳、氮、硫等元素循环的热区。硫酸盐还原菌(sulfate-reducing prokaryotes，SRPs)是地球最古老的微生物生命形式之一，在推动早期地球地质演化以及现代生物地球化学循环中发挥关键作用，但其在红树林湿地还缺乏全面深入研究。本文基于Genome Taxonomy Database中原核生物基因组的挖掘，系统总结了硫酸盐还原菌的类群，梳理了近年来国内外红树林中硫酸盐还原菌的分布情况及影响其分布的因素，分析了硫酸盐还原菌在红树林生态系统的碳、氮、硫及铁等元素地球化学循环中的作用，并对硫酸盐还原菌未来的研究方向进行了展望，以期为深入研究硫酸盐还原菌参与驱动的元素生物地球化学循环及其耦合机制提供参考。

Abstract:

Mangrove ecosystems are important coastal wetlands with highly efficient nutrient dynamics in the tropics and subtropics, and the hot zones driving the cycling of elements such as carbon, nitrogen, and sulfur. Sulfate-reducing prokaryotes (SRPs), one of the oldest microbial life forms on Earth, play a key role in driving early geological evolution and modern biogeochemical cycles of the Earth, while their role in mangrove wetlands remains to be studied. Only by fully understanding the processes and characteristics of the element biogeochemical cycles that SRPs participate in mangrove ecosystems can we capture the key aspects and clarify the coupling mechanisms. The development of bioinformatics has led to the discovery of more and more uncultured SRPs. In this paper, we systematically summarized the classification of sulfate-reducing bacteria and expand the taxa of SRPs based on the Genome Taxonomy Database prokaryotic genomes. We then introduced the distribution of SRPs in mangroves at home and abroad in recent years and the factors affecting the distribution to reveal the horizontal distribution diversity of SRPs in mangrove ecosystems. Further, we expounded the role of SRPs in the intertwined cycles of carbon, nitrogen, sulfur, and iron in mangrove wetlands, with emphasis on the molecular processes of SRPs in the sulfur cycle, especially dissimilatory sulfate reduction. Finally, we made an outlook on the future research directions of SRPs, aiming to provide references for further research on the element biogeochemical cycling and coupling driven by SRPs.