大肠杆菌在葡萄糖和甘油碳源培养条件下的基因表达谱分析

Gene Expression Profling Analysis of Escherichia coli under the Conditions of Glucose and Glycerol Carbon Source Culture

【目的】探讨葡萄糖和甘油碳源对大肠杆菌(Escherichia coli)基因表达谱的影响。【方法】通过基因表达数据库GEO下载基因芯片数据集GSE2037和高通量测序数据集GSE156143,分别对两个数据集中的葡萄糖和甘油碳源样本进行差异表达基因筛选,对筛选到的差异表达基因进行并集后,进行GO功能富集分析、KEGG通路富集分析以及蛋白质相互作用网络构建。【结果】筛选出701个差异表达基因,差异表达基因主要富集于小分子分解代谢过程、碳水化合物运输、趋化性等生物学过程,细胞器、细菌型鞭毛、甲基接受趋化蛋白复合物等细胞组分,离子跨膜转运蛋白活性、碳水化合物结合、肌动活动等分子功能以及不同环境中的微生物代谢和ABC转运体相关通路。此外,筛选出的14个核心基因在鞭毛合成和趋化中发挥作用。【结论】大肠杆菌在葡萄糖和甘油碳源培养条件下具有不同的基因表达模式,所确定的14种与趋化和鞭毛合成有关的基因有助于进一步揭示大肠杆菌在应对不同营养环境变化时采取的分子调控机制。

[Purposes]To investigate the effects of glucose and glycerol carbon sources on the gene expression profiles of Escherichia coli. [Methods]The gene chip dataset GSE2037 and the high-throughput sequencing dataset GSE156143 were downloaded from the gene expression database GEO, and the differentially expressed genes were screened for the glucose and glycerol carbon source samples in the two datasets, respectively. After merging, GO(gene ontology) functional enrichment analysis, KEGG(kyoto encyclopedia of genes and genomes) pathway enrichment analysis, and protein-protein interaction networks(PPI) were performed. [Findings]701 differentially expressed genes were screened out. The differentially expressed genes are mainly enriched in the biological processes related to small molecule catabolic process, carbohydrate transport, chemotaxis, cellular component related to organelle, bacterial-type flagellum, methyl accepting chemotaxis protein complex, molecular function related to ion transmembrane transporter activity, carbohydrate binding, motor activity. And microbial metabolism in diverse environments, ABC transporters pathways.In addition, 14 core genes were screened out, which played roles in flagella synthesis and chemotaxis. [Conclusions]E. coli has different gene expression patterns under the conditions of glucose and glycerol carbon sources. The identified 14 genes related to chemotaxis and flagella synthesis are helpful to further reveal the molecular regulatory mechanism adopted by E.coli in response to different nutrient environment changes.