biostudies-literatureLi QOpen Fund of Key Laboratory of Agro-ecological Processes in Subtropical Region Chinese Academy of SciencesHunan Province Science and Technology PlanChina Postdoctoral Science FoundationNational Natural Science Foundation of ChinaWuxi University Research Start-up Fund for High-level TalentsNational Key Research and Development Program of ChinaAustralian Research Council Future Fellowshipwraf183https://www.ebi.ac.uk/biostudies/studies/S-EPMC12449052biostudies-literatureUnknown19(1)Enteric methane emissions are energy losses from farmed ruminants and contribute to global warming. Diverting electrons and H2 flow toward beneficial fermentation products would mitigate ruminal methane emissions while improving feed efficiency. Acetogens can direct H2 and electrons to acetate production via the Wood-Ljungdahl pathway, but methanogens have more competitive H2 affinities. Thus, it is unclear how acetogenesis contributes to the rumen fermentation. An analysis of 2102 globally derived rumen metagenomes from multiple ruminant species revealed that putative acetogens were phylogenetically diverse and capable of using carbohydrates or H2 as electron donors. The metabolic versatility of these acetogens may enable them to outcompete methanogens with lower versatility. Through animThe ISME journalMetabolic versatility enables acetogens to colonize ruminants with diet-driven niche partitioning.PMC12449052ISA2021203FT24010050232525054, U22A20512, 321611430282023YFD1300902GZC202517582022NK2021, 2022RC3058Li QMuller VZhang SJiao JZhou XJanssen PHConrad RFu BWang MUngerfeld EMLi SWang RGreening CTan ZZhang XWang WfalseMetabolic versatility enables acetogens to colonize ruminants with diet-driven niche partitioning.Enteric methane emissions are energy losses from farmed ruminants and contribute to global warming. Diverting electrons and H2 flow toward beneficial fermentation products would mitigate ruminal methane emissions while improving feed efficiency. Acetogens can direct H2 and electrons to acetate production via the Wood-Ljungdahl pathway, but methanogens have more competitive H2 affinities. Thus, it is unclear how acetogenesis contributes to the rumen fermentation. An analysis of 2102 globally derived rumen metagenomes from multiple ruminant species revealed that putative acetogens were phylogenetically diverse and capable of using carbohydrates or H2 as electron donors. The metabolic versatility of these acetogens may enable them to outcompete methanogens with lower versatility. Through anim2025-01-01T00:00:00Z2025 Jan2026-06-04T07:30:24.313Z2026-06-04T03:06:05.484ZS-EPMC124490524088846510.1093/ismejo/wraf183