Data from: Cryptic diversity of cellulose-degrading gut bacteria in industrialized humans

Humans, like all mammals, depend on the gut microbiome for digestion of cellulose, the main component of plant fiber, but evidence for cellulose fermentation in the human gut is scarce. We have identified ruminococcal species in the gut microbiota of human populations that assemble functional multi-enzymatic cellulosome systems capable of degrading plant cell wall polysaccharides. One of these species, which is strongly associated with humans, likely originated in the ruminant gut and was subsequently transferred to the human gut potentially during domestication, where it underwent diversification and diet-related adaptation through the acquisition of genes from other gut microbes. Collectively, these species are abundant and widespread among ancient humans, hunter-gatherers, and rural populations, but are extremely rare in populations from industrialized societies, suggesting potential disappearance in response to the westernized lifestyle.与所有哺乳动物一样，人类也依赖肠道微生物组（gut microbiome）完成植物纤维主要成分纤维素的消化，但人类肠道内纤维素发酵的相关证据却十分匮乏。我们在人类群体的肠道微生物群（gut microbiota）中鉴定出了瘤胃球菌属物种，这些物种能够组装具备降解植物细胞壁多糖功能的多酶纤维小体（cellulosome）系统。其中一种与人类高度关联的物种，其起源极有可能位于反刍动物肠道，随后可能在驯化过程中转移至人类肠道，并在此过程中通过获取其他肠道微生物的基因，经历了物种分化与饮食适应性演化。综上而言，这些物种在古代人类、狩猎采集人群以及农村人口中分布广泛且丰度较高，但在工业化社会的人群中却极为罕见，这表明它们可能因西式生活方式而逐渐消失。