休哈塔假丝酵母中甲酸抑制的目标基因发掘

Discovery of the target genes inhibited by formic acid in Candida shehatae

摘要:

摘要:【目的】探究甲酸对木糖乙醇发酵模式菌株休哈塔假丝酵母基因转录的影响规律，发掘抑制的目标基因及抑制特征。【方法】基于该酵母葡萄糖、木糖代谢转录组的研究成果，结合细胞代谢途径和人工基因比对筛选出乙醇发酵相关基因，再通过RQ-PCR对梯度甲酸抑制条件下的上述基因进行定量分析，进而发掘出甲酸抑制的目标基因。【结果】共筛选出42 个相关基因，经RQ-PCR 定量分析最终确定受甲酸显著抑制的基因10个，上调基因5个。【结论】在基因转录水平上，休哈塔假丝酵母中甲酸显著抑制的基因按照抑制强度降序排列为XYL2、ACS、RKI、TAL、GND1、TKL、ZWF1、XYL1、PDH 和PDC，按照上调强度降序排列为ALD、GLK、MDH、PFK、ADH。

Abstract:

Abstract:［Objective］At transcriptional level，the inhibitory effects of formic acid was investigated on Candida shehatae，a model yeast strain capable of fermenting xylose to ethanol． Thereby，the target genes were regulated by formic acid and the transcript profiles were discovered．［Methods］ On the basis of the transcriptome data of C. shehatae metabolizing glucose and xylose，the genes responsible for ethanol fermentation were chosen as candidates by the combined method of yeast metabolic pathway analysis and manual gene BLAST search．These candidates were then quantitatively detected by RQ-PCR technique to find the regulating genes under gradient doses of formic acid．［Results］By quantitative analysis of 42 candidate genes，we finally identified 10 and 5 genes as markedly down-regulated and up-regulated targets by formic acid，respectively.［Conclusion］With regard to gene transcripts regulated by formic acid in C．shehatae，the markedly down-regulated genes ranking declines as follows: xylitol dehydrogenase (XYL2)，acetyl-CoA synthetase (ACS)，ribose-5-phosphate isomerase (RKI)，transaldolase (TAL)，phosphogluconate dehydrogenase (GND1)，transketolase (TKL)，glucose-6-phosphate dehydrogenase (ZWF1)，xylose reductase (XYL1)，pyruvate dehydrogenase (PDH) and pyruvate decarboxylase (PDC); and a declining rank for up-regulated gens as follows: fructose-bisphosphate aldolase (ALD)，glucokinase (GLK)，malate dehydrogenase (MDH)，6-phosphofructokinase (PFK) and alcohol dehydrogenase (ADH)．