napF3调控腾冲嗜热厌氧杆菌热适应机制

napF3 regulates thermophilic mechanism of Thermoanaerobacter tengcongensis

摘要:

【目的】研究腾冲嗜热厌氧杆菌napF3在不同温度下的功能。【方法】通过同源重组构建腾冲嗜热厌氧杆菌的ΔnapF3株，观察并比较其在50、60、75和80℃下野生株和ΔnapF3株的生长趋势。通过转录组测序确定ΔnapF3株与野生株在75℃的差异表达基因。采用荧光定量PCR分析野生株和ΔnapF3株中13个基因和3个sRNA在50、60、75和80℃下的转录水平。【结果】成功构建了ΔnapF3株，生长曲线结果显示其在50℃和80℃不生长，60℃和75℃生长速度显著减缓。转录组结果显示：有899个基因表达发生差异，包括363个上调基因和536个表达下调基因，这些差异表达基因主要富集在缬氨酸、亮氨酸和异亮氨酸的生物合成、ABC运输工具、双组分系统、脂肪酸合成、硫胺素代谢等途径，并发现与嗜热机制相关的13个基因和3个非编码RNA的转录水平在特定温度下发生了变化。【结论】腾冲嗜热厌氧杆菌napF3在热适应过程中发挥重要作用。

Abstract:

[Objective] To study the role of napF3 in Thermoanaerobacter tengcongensis at different temperatures.[Methods]We constructed ΔnapF3 from T.tengcongensis by homologous recombination and observed the growth of ΔnapF3 at 50℃,60℃,75℃,and 80℃.Transcriptome sequencing was employed to identify the differentially expressed genes (DEGs) between ΔnapF3 and the wild type (WT) at 75℃.real-time PCR was conducted to measure the transcriptional levels of 13 genes and 3 sRNAs in WT and ΔnapF3 at 50℃,60℃,75℃,and 80℃.[Results] ΔnapF3 was successfully constructed,and it showcased suspended growth at 50℃ and 80℃ and slow growth at 60℃ and 75℃.A total of 899 DEGs between WT and ΔnapF3 at 75℃ were identified,including 363 genes with up-regulated expression and 536 genes with down-regulated expression.These DEGs were mainly involved in the biosynthesis of valine,leucine and isoleucine,ABC transporters,two-component system,fatty acid synthesis,thiamine metabolism and other pathways.The transcriptional levels of 13 genes and 3 sRNAs related to the thermophilic mechanism changed under specific temperatures.[Conclusion] napF3 plays a role in the thermophilic adaptation of T.tengcongensis.