无铜饲料对小鼠肠道菌群的影响

铜是动物机体必需的金属元素，参与重要的代谢反应。本试验旨在研究无铜饲料对小鼠肠道微生物菌落组成和相关代谢通路的影响，选择健康、体重相近、遗传背景为野生型C57BL/6J的成年公鼠20只，随机分为2组，试验组和对照组各10只。待小鼠适应性饲养1周后用无铜饲料饲喂，对照组饲喂25 mg/L含铜水，试验组饲喂无铜水，试验期30 d。试验期结束时，尾静脉采血进行铜蓝蛋白含量的测定，并采集小鼠新鲜盲肠内容物利用高通量测序技术对小鼠的盲肠内容物16S rRNA基因组进行分析。结果显示，与对照组相比，无铜组小鼠血清铜蓝蛋白含量极显著降低（P < 0.001）。无铜组小鼠盲肠微生物菌群在门、属水平分别与对照组有5和43个差异显著菌群（P < 0.05）；通过差异菌群功能预测分析发现，两组共有19种KEGG二级代谢通路差异显著（P<0.05），其中与代谢相关的功能是脂代谢、甘氨酸生物合成与代谢、多酮类化合物和萜类化合物代谢、其他次生代谢产物的生物合成和氨基酸代谢，说明饲料中铜的缺失可以改变少数肠道菌群的组成及其功能，本试验为研究铜在小鼠肠道菌群结构及代谢中的功能提供了重要思路。

Effect of Copper Deficient Diet on Gut Microbiota in Mice

Copper is an essencial metal for animals to maintain fat metabolism and other important reactions.In order to study the effect of copper deficient diets on composition of intestinal microbiota and their metabolic pathways, 20 health C57BL/6 adult mice with similar body weight were chosen and fed chow diet for 7 d,and then divided into 2 groups.The mice in control group fed with copper deficient diet and 25 mg/L copper water while the experimental group mice were fed copper deficient diet and copper free water for one month.At the end of the test,the blood samples were collected to determine the ceruloplasmin content,and the caecum content were used to analyze the 16S rRNA genome by high throughput sequencing. The results showed that compared with control group,the ceruloplasmin content in experimental group was extremely significantly decreased (P < 0.001).And there were 5 siginificant differences microorganism in phylum level and 43 in genus level (P<0.05). There were 19 significant different pathways in the second grade of KEGG (P<0.05),in which metabolic-related functions were lipid metabolism, glycine biosynthesis and metabolism,metabolism of terpenoids and polyketides,biosynthesis of other secondary metabolisms and amino acid metabolism,indicating that the absence of copper in diets could alter the structure of some microbial flora and the changes of the relevant functions. It provided an important idea for studying the function of copper in the structure and metabolism of intestinal colonies in mice.