The mammal intestinal microbiota is involved in various physiological processes and plays a key role in host environment adaption. However, for non-human primates (NHPs), little is known about their gut microbial community in high-altitude environments and even less about their adaption to such habitats. We characterised the gut microbial community of rhesus macaques from multiple high-altitude environments and compared it to those of low-altitude populations. We collected faecal samples of rhesus macaques from four high-altitude populations (above 3000 m) and three low-altitude populations (below 500 m). By calculating the alpha diversity index, we found that high-altitude populations exhibited a higher diversity. Statistical analysis of beta diversity indicated significant differences between high- and low-altitude populations. Significant differences were also detected at the phylum and family levels. At the phylum level, the high-altitude gut microbial community was dominated by Firmicutes (63.42%), while at low altitudes, it was dominated by Bacteroidetes (47.4%). At the family level, the high-altitude population was dominated by Ruminococcaceae (36.2%), while the low-altitude one was dominated by Prevotellaceae (39.6%). Some families, such as Christensenellaceae and Rikenellaceae, were consistently higher abundant in all high-altitude populations. We analysed the overlap of operational taxonomic units (OTUs) in high-altitude populations and determined their core OTUs (shared by all four high-altitude populations). However, when compared with the low-altitude core OTUs, only 65% were shared, suggesting a divergence in core OTUs. Function prediction indicated a significant difference in gene copy number of 35 level-2 pathways between high- and low-altitude populations; 29 of them were higher in high altitudes, especially in membrane transport and carbohydrate metabolism. The gut microbial community of high-altitude rhesus macaques was significantly distinct from that of low-altitude populations in terms of diversity, composition and function. High-altitude populations were dominated by Firmicutes and Ruminococcace, while in low-altitude populations, Bacteroidetes and Prevotellaceae were dominant. The difference in gut microbiota between these two populations may be caused by differences in host diet, environmental temperature and oxygen pressure. These differentiated gut microbial microorganisms may play a critical role in the adaptive evolution of rhesus macaques to high-altitude environments.

中文翻译：

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高海拔环境中恒河猴肠道微生物群落的特征。


哺乳动物肠道微生物群参与多种生理过程，在宿主环境适应中发挥关键作用。然而，对于非人类灵长类动物（NHP）来说，人们对它们在高海拔环境中的肠道微生物群落知之甚少，对它们对这种栖息地的适应更是知之甚少。我们对来自多个高海拔环境的恒河猴肠道微生物群落进行了表征，并将其与低海拔人群进行了比较。我们从四个高海拔种群（3000 m以上）和三个低海拔种群（500 m以下）收集了恒河猴的粪便样本。通过计算α多样性指数，我们发现高海拔人群表现出更高的多样性。 β多样性的统计分析表明高海拔和低海拔人群之间存在显着差异。在门和科水平上也发现了显着差异。在门水平上，高海拔地区肠道微生物群落以厚壁菌门（63.42%）为主，而低海拔地区则以拟杆菌门（47.4%）为主。在科一级，高海拔种群以瘤胃科为主（36.2%），低海拔种群以普氏菌科为主（39.6%）。一些科，例如 Christensenellaceae 和 Rikenellaceae，在所有高海拔种群中的数量始终较高。我们分析了高海拔种群中操作分类单元（OTU）的重叠，并确定了它们的核心OTU（由所有四个高海拔种群共享）。然而，与低空核心OTU相比，只有65%是共享的，这表明核心OTU存在分歧。 功能预测表明，高海拔人群和低海拔人群的35条2级通路基因拷贝数存在显着差异；其中29个在高海拔地区较高，尤其是膜运输和碳水化合物代谢方面。高海拔恒河猴肠道微生物群落在多样性、组成和功能方面与低海拔猕猴肠道微生物群落存在显着差异。高海拔种群以厚壁菌门和瘤胃球菌门为主，低海拔种群以拟杆菌门和普氏菌科为主。这两个人群肠道微生物群的差异可能是由宿主饮食、环境温度和氧压的差异引起的。这些分化的肠道微生物可能在恒河猴对高海拔环境的适应性进化中发挥关键作用。