宏基因组测序分析东寨港红树林淤泥和水体微生物的多样性

Revealing Microorganism Diversity of Silt and Water in Dongzhaigang Mangroves by Metagenome Sequencing

为深入了解海南东寨港红树林生态系统微生物多样性及其在氮、磷、硫等代谢循环中的功能特点,本研究采用宏基因组测序,从物种注释与丰度、群落功能及多样性指数等角度,分析红树林淤泥和水体生境中微生物群落结构及生态功能的特异性。结果显示,在淤泥中检测到53个门、909个属的微生物类群,有3个占比超过1%的优势门类,其中变形杆菌门为83.78%,处于绝对优势,其下的12个优势属全部来自变形杆菌门;不动杆菌属是聚磷微生物的主要类群,其在淤泥中含量是水体的107.7倍,硫氧化单胞菌属、脱硫杆菌属是硫化物代谢的主要菌属,主要存在于淤泥生境当中。在水体中检测到64个门、1 522个属,包括13个优势门类、7个优势属;Nitrospinae和硝化螺旋菌门是亚硝酸盐氧化代谢的关键类群,两者在水体中占比分别是淤泥中的28.1倍和6.8倍。多样性评估得知,水体样品中的Shannon Wiener指数和Simpson指数均高于淤泥样品,两样品在属分类学单元上的Simpson指数趋近于1,表明红树林生态系统具有非常高的微生物多样性,水体生境的微生物多样性高于淤泥;亚硝酸盐的微生物代谢循环主要发生在水体生境中,微生物对磷的富集作用和硫化合物的氧化还原代谢主要发生在淤泥生境中。本研究有助于认识东寨港红树林湿地生境中的微生物资源状况,为保护红树林生态系统和开发利用其中的微生物资源提供依据。

To further understand the microbial diversity of Dongzhaigang mangrove ecosystem and its function for nitrogen,phosphorus and sulfur metabolic circulation,the study analysed the differences of microbial community structures and ecological function specificities between mangroves silt and water habitat based on the species annotation and abundance,community function and diversity index,following metagenomic sequencing for it.The results showed:in this inverstigation,53 phyla and 909 genera of microorganism groups were detected in silt,of which three dominant phyla accounted for more than 1% of the total,and proteobacteria,whose proportion was up to 83.78%,were in absolute superiority;all 12 dominant genera were from the proteobacteria;Acin etobacter is the main source of polyphosphate microorganisms,the content of which in the silt is 107.7 times as much as that in the water;Sulfurimonas,desulfobacterium were the main genera of sulfide metabolism,which are mainly in silt habitat.64 phyla and 1 522 genera were detected in water,including 13 dominant phyla and 7 dominant genera.Nitrospinae and nitrospira were the key groups of nitrite oxidation metabolism.The proportion of them in water were 28.1 times and 6.8 times as much as that in silt.Diversity assessment showed that the Shannon Wiener index and Simpson index of water samples were higher than that of silt samples,and the Simpson index of genus-group taxa from both two samples were on the verge of 1.In conclusion,mangrove ecosystem has a very high diversity of microorganisms and microbial diversity of the water habitats is higher than that of the silt.The microbial metabolic cycle of nitrite mainly occurs in the water habitats.The enrichment of phosphorus by microorganisms and the redox of sulfur compounds metabolism mainly occurs in silt habitats.This study helps to understand the status of microbial resources in the mangrove wetland habitat in Dongzhaigang,and provides a basis for protecting mangrove ecosystems and exploitatig and utilizing the microbial resources therein.