环境空气暴露对猪粪悬液中菌群及代谢物的影响

Effects of aerobic and anaerobic FMT preparation on fecal microbiota and metabolite profiles in swine

目的研究环境空气暴露对制备的粪悬液中微生物及代谢物的影响。方法收集无特定病原体级巴马小型猪粪便:(1)未处理组(C组);(2)有氧暴露处理组(T1组);(3)厌氧暴露处理组(T2组)。利用扩增子测序技术和非靶向代谢组比较各组粪样的微生物群落组成及代谢产物。结果(1)T1和T2组粪悬液制备操作均保存了新鲜粪便中(C组)的全部细菌门,仍以厚壁菌门和拟杆菌门细菌为主,但显著降低了密螺旋体属细菌的丰度;(2)猪粪便中以子囊菌门、担子菌门真菌为主,粪悬液制备显著提高了猪粪便中子囊菌门真菌的丰度;有氧暴露处理去除了猪粪便中节单菌属真菌。(3)LC-MS结果显示:正负离子模式下各识别出402、195种代谢物,其中T1∶C代谢集、T2:C代谢集的差异代谢物分别为155和201个。结论猪粪悬液制备时间虽然不长,但有氧暴露对样本中真菌群落丰度的影响高于厌氧暴露,都显著地降低Treponema和Spirochaetes等有害菌群和相关代谢产物的丰度,提高了FMT的安全性。

Objective Fecal microbiota transplantation(FMT)is a promising,but immature intervention in the current pig production.The aim of this study was to investigate the effects of aerobic and anaerobic FMT preparation(T1 group and T2 group,respectively)on fecal microbiota and metabolite profiles of SPF Bama mini pigs.Methods Amplicon sequencing and untargeted metabolomics method were used to reveal the effects of aerobic and anaerobic FMT preparation(T1 group and T2 group,respectively)on fecal microbiota and metabolite profiles of SPF Bama mini pigs.Results(1)The two FMT preparation method preserved all the bacterial phyla in untreated pig slurries(C group).Firmicutes and Bacteroidetes constituted the top two phyla in the gut microbiota in all groups,and FMT preparation result ed in a significant decrease of Treponema bacteria.(2)In untreated pig slurries,the two most abundant fungal phyla were Ascomycota and Basidionmycota.FMT preparation significantly increased the relative abundance of Ascomycota,and aerobic FMT preparation removed the Wallemia genus.These changes in microbial community did not affect the functional contributions.(3)A total of 402 and 195 characteristic metabolites were respectively detected by positive and negative mode liquid chromatograohy-mass spectrometry,including Lipids and lipid molecules,and Organoheterocyclic compounds.Disturbance of amino acid metabolism,and lipid metabolism were the most significant in T1 versus C comparison,and T2 versus C comparison,155 and 201 confirmed differential metabolites using reference compounds were identified,respectively.Highly positive correlated metabolites with Spearman correlation coefficient r>0.6 are connected with Trepronema_2 in T1 versus C and T2 versus C comparisons,and highly negative correlated metabolites with r<-0.4 are connected with Ruminococcaceae NK4 A214 group in T1 versus C and T2 versus C comparisons.Conclusions Although the FMT preparation time is short,the effect of short aerobic exposure on the abundance of fungal communities in the samples was higher than that of short anaerobic exposure,and the relative abundance of harmful bacteria such as Treponema and Spirochaetes and related metabolites were effectively reduced,which could improve the safety of FMT.