Thermal swamps are unique ecosystems where geothermally warmed waters mix with decomposing woody biomass, hosting novel biogeochemical-cycling and lignin-degrading microbial consortia. Assembly of shotgun metagenome libraries resolved 351 distinct genomes from hot-spring (30–45 °C) and mesophilic (17 °C) sediments. Annotation of 39 refined draft genomes revealed metabolism consistent with oligotrophy, including pathways for degradation of aromatic compounds, such as syringate, vanillate, p-hydroxybenzoate, and phenol. Thermotolerant Burkholderiales, including Rubrivivax ssp., were implicated in diverse biogeochemical and aromatic transformations, highlighting their broad metabolic capacity. Lignin catabolism was further investigated using metatranscriptomics of sediment incubated with milled or Kraft lignin at 45 °C. Aromatic compounds were depleted from lignin-amended sediment over 148 h. The metatranscriptomic data revealed upregulation of des/lig genes predicted to specify the catabolism of syringate, vanillate, and phenolic oligomers in the sphingomonads Altererythrobacter ssp. and Novosphingobium ssp., as well as in the Burkholderiales genus, Rubrivivax. This study demonstrates how temperature structures biogeochemical cycling populations in a unique ecosystem, and combines community-level metagenomics with targeted metatranscriptomics to identify pathways with potential for bio-refinement of lignin-derived aromatic compounds. In addition, the diverse aromatic catabolic pathways of Altererythrobacter ssp. may serve as a source of thermotolerant enzymes for lignin valorization.

地热沼泽是独特的生态系统，地热加热的水与分解的木质生物质混合在一起，承载着新的生物地球化学循环和木质素降解微生物群落。鸟枪法宏基因组文库的组装解决了来自温泉 (30–45 °C) 和嗜温 (17 °C) 沉积物的 351 个不同的基因组。对 39 个精制基因组草图的注释揭示了与寡营养相一致的新陈代谢，包括芳香族化合物的降解途径，例如丁香酸盐、香草酸盐、对羟基苯甲酸盐和苯酚。耐热伯克霍尔德氏菌目，包括Rubrivivaxssp., 涉及多种生物地球化学和芳香转化，突出了它们广泛的代谢能力。使用在 45 °C 下与研磨或硫酸盐木质素孵育的沉积物的元转录组学进一步研究木质素分解代谢。在 148 小时内，木质素改良沉积物中的芳香族化合物被耗尽。宏转录组数据显示des / lig基因的上调预计会指定鞘氨醇单胞菌 Altererythrobacter ssp 中丁香酸盐、香草酸盐和酚类低聚物的分解代谢。和Novosphingobium ssp.，以及Burkholderiales属，Rubrivivax. 本研究展示了温度如何在独特的生态系统中构建生物地球化学循环种群，并将社区水平的宏基因组学与靶向元转录组学相结合，以确定具有木质素衍生芳香族化合物生物精制潜力的途径。此外，Altererythrobacter ssp 的多种芳香分解代谢途径。可作为木质素增值的耐热酶的来源。