环境胁迫和非胁迫条件下类植物乳杆菌转录组分析

Transcriptome analysis of Lactobacillus paraplantarum L-ZS9 under environmental stress and control conditions

摘要:

【背景】类植物乳杆菌L-ZS9是一株在食品发酵与保鲜方面具有潜在应用价值的产细菌素益生菌。【目的】深入了解环境胁迫影响类植物乳杆菌L-ZS9细菌素合成的重要相关调节基因的信息。【方法】通过高通量测序技术对类植物乳杆菌转录组进行测序，对所有转录本进行COG (Clusters of Orthologous Groups)、GO (Gene Ontology)和KEGG (Kyoto Encyclopedia of Genes and Genomes)分类和Pathway注释。 【结果】 转录组测序显示2个样品基因覆盖度都在90%以上，差异表达基因927个，其中744个上调，183个下调。KEGG分析结果表明，649个差异表达基因中68个集中在“ABC转运途径”，占10.48%，其中3个基因表达上调超过16倍，1个基因表达下调超过1/16，暗示类植物乳杆菌L-ZS9细菌素合成与“ABC转运途径”密切相关。另外多个孤儿基因表达变化也超过16倍，有的甚至表达上调达万倍。【结论】进一步拓展了类植物乳杆菌的基因信息，为类植物乳杆菌细菌素代谢途径和逆境反应研究提供了坚实的基础。

Abstract:

[Background] Lactobacillus paraplantarum L-ZS9, which could produce bacteriocin, would be used in food preservative and fermentation. [Objective] To understand expression characters of regulated genes of bacteriocin synthesis under environment stress conditions for Lactobacillus paraplantarum L-ZS9. [Methods] We used high-throughput sequencing technology to sequence its transcriptome. Based on the Clusters of Orthologous Groups (COG), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, we carried out functional annotation and classification, pathway annotation. [Results] The results suggested that distribution of genes’ coverage is beyond 90% of two samples, the total genes with expression difference were 927, of which 744 were up regulation and 183 down regulation. KEGG pathway analysis showed that 68 out of the 649 genes with different expression levels were classed into ABC transport pathway, accounting for 10.48% and three genes were up regulated beyond 16 times and one was down regulated beyond 1/16. In addition, expression of some orphan genes changed with 16 times up or down-regulation, some even could increase more than 10 000 times. [Conclusion] This study further improved the gene information and laid the foundation of bacteriocin metabolic pathway and stress respond research for Lactobacillus paraplantarum.