Investigation on the aerobic methanotrophic community and the dominant taxon Methylomarinum in seagrass ecosystem

作者：Tongyin Liang, Junde Dong, Weiguo Zhou, Xiaofang Huang, Hongbin Liu, Yuhang Zhang, Qingsong Yang, Manzoor Ahmad, Luxiang Chen, Juan Ling · 发表于：Environmental Microbiome · 年份：2025 · DOI：10.1186/s40793-025-00736-z · 被引用次数：1 · 研究领域：Methane Hydrates and Related Phenomena、Microbial metabolism and enzyme function、Microbial Community Ecology and Physiology

BACKGROUND: Methanotrophs are a key biological methane sink, and aerobic methanotrophs critically reduce wetland methane emissions under global climate change. However, despite their ecological significance, investigations on aerobic methanotrophs within seagrass ecosystems remain scant. In this study, microcosmic culture experiments were used to assess aerobic methane oxidation (AMO) potential and its drivers across a vertical gradient of seagrass sediments. Moreover, the methanotrophic community structure was characterized by amplicon sequencing, and the dominant methanotroph's metagenome-assembled genome (MAG) and metabolic pathway was investigated. RESULTS: -N) decreased with sediment depth, and was suggested by structural equation modeling (SEM) to significantly contribute to the vertical methane oxidation variability. Microbial community structure analysis revealed that type I methanotrophs were stimulated by methane addition and significantly impacted the oxidation of elevated methane, with Methylomarinum being the dominant taxon. Through metagenomic analysis, we assembled a phylogenetically novel methanotroph, Candidatus Methylomarinum sp. MAG81, which is distantly related to the extant Methylomarinum vadi IT-4. We conducted a comparative analysis of the two genomes and discovered that MAG81 not only possesses the capability for methane oxidation but also has the ability to participate in methanol oxidation via Xox-MDH. Furthermore, MAG81 also harbors nitrogen metabol...