Proglacial lake is an emergent source of the second most important greenhouse gas methane as the climate continues to warm,and syntrophic bacteria play a crucial role in the sediment organic matter degradation and met...Proglacial lake is an emergent source of the second most important greenhouse gas methane as the climate continues to warm,and syntrophic bacteria play a crucial role in the sediment organic matter degradation and methane production.However,our understanding of syntrophic bacteria in the proglacial lake sediments is limited.Here,we combined 16S rRNA gene amplicon sequencing,metagenomics,and metatranscriptomics to explore the diversity,function,and activity of syntrophic propionate-and butyrate-oxidizing bacteria(SPOB and SBOB)in sediments of a glacier-fed proglacial lake on the south Qinghai-Tibet Plateau.We identified a diverse array of putative SPOB and SBOB with pronounced spatial and temporal variations,many of which were central in microbial co-occurrence networks.The most abundant SBOB were Syntrophus,Syntrophorhabdus,and unclassified_Syntrophales,and the dominant SPOB included unclassified_Syntrophobacterales,Smithella,and Syntrophobacter.Lake hydrology,water depth,and associated physicochemical properties shape the spatial patterns of sediment syntrophic bacterial communities.Genome-resolved metagenomics revealed 21 and 4 genus-level novel lineages for SPOB and SBOB,respectively.Transcriptomic evidence highlighted high activity of the uncharacterized genera UBA1429(Anaerolineae)and E44-bin15(Dehalococcoidia)in propionate oxidation,and JAPLJM01(Syntrophia)as a dominant player in butyrate oxidation.This study provides the first insight into syntrophic oxidizers in proglacial lake sediments,advancing our understanding of carbon cycling and methane emission in cryosphere aquatic ecosystems.展开更多
基金supported by the National Natural Science Foundation of China for Excellent Young Scientists Fund Program(Grant No.42222105)the National Natural Science Foundation of China General Program(Grant No.42171144),the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(Grant No.2021QZKK0100)+1 种基金the Key Research and Development Plan of Xizang Autonomous Region(Grant No.XZ202301ZY0008G)the Global Ocean Negative Carbon Emissions(Global ONCE)Program.
文摘Proglacial lake is an emergent source of the second most important greenhouse gas methane as the climate continues to warm,and syntrophic bacteria play a crucial role in the sediment organic matter degradation and methane production.However,our understanding of syntrophic bacteria in the proglacial lake sediments is limited.Here,we combined 16S rRNA gene amplicon sequencing,metagenomics,and metatranscriptomics to explore the diversity,function,and activity of syntrophic propionate-and butyrate-oxidizing bacteria(SPOB and SBOB)in sediments of a glacier-fed proglacial lake on the south Qinghai-Tibet Plateau.We identified a diverse array of putative SPOB and SBOB with pronounced spatial and temporal variations,many of which were central in microbial co-occurrence networks.The most abundant SBOB were Syntrophus,Syntrophorhabdus,and unclassified_Syntrophales,and the dominant SPOB included unclassified_Syntrophobacterales,Smithella,and Syntrophobacter.Lake hydrology,water depth,and associated physicochemical properties shape the spatial patterns of sediment syntrophic bacterial communities.Genome-resolved metagenomics revealed 21 and 4 genus-level novel lineages for SPOB and SBOB,respectively.Transcriptomic evidence highlighted high activity of the uncharacterized genera UBA1429(Anaerolineae)and E44-bin15(Dehalococcoidia)in propionate oxidation,and JAPLJM01(Syntrophia)as a dominant player in butyrate oxidation.This study provides the first insight into syntrophic oxidizers in proglacial lake sediments,advancing our understanding of carbon cycling and methane emission in cryosphere aquatic ecosystems.
