中温大曲发酵过程中细菌群落结构解析及功能预测

Bacterial community structure analysis and functional prediction during fermentation of medium-temperature Daqu

利用高通量测序技术解析了中温大曲发酵过程中的细菌群落结构、功能及表型变化。结果表明:中温大曲细菌群落主要由魏斯氏菌属、葡萄球菌属、埃希氏菌属、乳杆菌属等组成;基于OTU水平可将中温大曲样品聚类为前期(0 d和3 d)、中期(9 d和13 d)和后期(30 d)3类;发酵前期以葡萄球菌属为主要优势菌,中期以魏斯氏菌属为主要优势菌,后期则以Muribaculum为主要优势菌;中温大曲细菌菌群的氨基酸转运和代谢、碳水化合物转运和代谢等基因功能丰度较高;与发酵中期相比,发酵前期和后期细菌菌群的细胞壁/膜/包膜生物发生、翻译后修饰、蛋白质折叠和伴侣蛋白等基因功能丰度较高;发酵前期大多为兼性厌氧菌,中期以好氧菌为主,后期则主要是厌氧菌。

Using high-throughput sequencing technology the changes in bacterial community structure,function and phenotype during the fermentation of medium-temperature Daqu were analyzed.The results showed that the bacterial community of medium-temperature Daqu was mainly composed of Welchiella,Staphylococcus,Escherichia,Lactobacillus,and so on;etc.Based on OTU level,the samples of medium-temperature Daqu could be clustered into three categories:three stages including early stage(0 d and 3 d),middle stage(9 d and 13 d)and late stage(30 d).Staphylococcus was the main bacteria in the early fermentation stage,weissella was the main dominant bacteria in the middle stage,and muribaculum was the main bacteria in the late fermentation stage.The functional prediction showed the bacterial sequences in the medium-temperature Daqu were abundant in functional proteins abundance of genes such as amino acid transport and metabolism,carbohydrate transport and metabolism from bacteria inhabiting medium-temperature Daqu was high.The bacterial community in the early and late fermentation stages had higher abundance in function gene protein function such as cell wall/membrane/envelope biogenesis,posttranslational modification,protein turnover,chaperones intracellular trafficking,secretion,and vesicular transport,defense mechanisms protein than in the middle fermentation stage.mostly Most microorganisms were facultative anaerobic bacteria in the early stage of fermentation while the aerobic bacteria and anaerobic bacteria dominated in the middle stage,and in the late stage,respectively.