食物中蛋氨酸含量对高原鼠兔肠道微生物群落的影响OA北大核心CSTPCD

The degradation of grasslands caused by overgrazing provides abundant protein food resources for the plateau pika(Ochotona curzoniae)and changes in the content of essential amino acids(especially methionine)in the food can af-fect the host intestinal microbial community.In this study,plateau pikas were fed with 0.26％and 0.45％methionine di-ets according to the methionine content in their stomach contents in different degraded grasslands for 50 days.Collected feces were used for metagenomics and non-targeted metabolomics analysis to evaluate the effects of high methionine treatment on intestinal microbial communities and metabolites of plateau pika.The results showed that there was no sig-nificant difference in the α and β diversity of the intestinal microbial community of plateau pikas in the high methionine group compared with the low methionine group,but the abundance of Candidatus_Saccharibacteria and Tenericutes was significantly increased and the functions of butyric acid metabolism,taurine,and hypotaurine metabolism were signifi-cantly expressed,and the up-regulated metabolites were mainly enriched in primary bile acid synthesis,ascorbic acid and aldehyde metabolism,Th 17 cell differentiation,taurine and hypotaurine metabolism,B cell receptor signaling pathway,T cell receptor signaling pathway,and NF-κB pathway.On the other hand,the carbohydrate metabolism function of pla-teau pika microbiota in the low methionine group was significantly expressed,and its up-regulated metabolites were mainly enriched in amino acid metabolism-related pathways.These results suggest that high methionine foods can change intestinal microbes and their metabolites,which may enhance the immune and reproductive performance of the host,and play an important role in improving the individual fitness and population size of plateau pikas.