酸、热胁迫条件下酸土脂环酸芽孢杆菌SOD基因的表达分析

Analysis of SOD Gene Expression in Alicyclobacillus acidoterrestris under Heat and Acid Stresses

本研究在克隆得到酸土脂环酸芽孢杆菌DSM 3922T SOD基因全序列的基础上,利用荧光实时定量PCR技术分别检测酸土脂环酸芽孢杆菌SOD基因在酸、热胁迫条件下的表达差异。结果表明:该基因在正常生长条件下组成性表达,在酸、热胁迫下表达量在短时间内迅速上调,酸胁迫0.5 h表达量为对照组的4.63倍,胁迫1 h表达量升至最高,为对照组的32.55倍,随后表达量迅速下调,胁迫5 h时表达量降至对照组的1.67倍。70℃热胁迫5 min时SOD基因相对表达量为对照组的2.81倍,胁迫25 min时表达量升至最高,为对照组的15.05倍,随后表达量下调,胁迫40 min时表达量降至对照组的4.93倍。酸土脂环酸芽孢杆菌SOD基因对酸、热环境胁迫具有快速反应的特点,表明酸土脂环酸芽孢杆菌SOD基因与该菌嗜热耐酸的独特生理适应机制密切相关。

Based on the complete sequence of the SOD gene cloned from Alicyclobacillus (A). acidoterrestris DSM 3922, quantitative real time polymerase chain reaction (PCR) was used to analyze the differences in SOD mRNA expression levels in A. acidoterrestris under acid and heat stresses. The results showed that the SOD gene of A. acidoterrestris was constitutively expressed under normal growth conditions and was quickly upregulated under acid and heat stress conditions. SOD expression level after 0.5 h of acid stress was 4.63 times higher than that of the control group and then increased to a maximum level, which was 32.55 times higher than that of the control group after one hour of acid stress. Subsequently, the SOD gene expression level rapidly decreased and was 1.67 times higher than that of the control group when acid stress was applied for five hours. When heat stress was applied at 70 for five minutes, the relative expression level of the SOD gene was 2.81 times higher than that of the control group and then increased to a maximum level, which was 15.05 times higher than that of the control after 25 minutes of heat stress. Subsequently, the SOD gene expression level rapidly decreased and was 4.93 times higher than that of control group when heat stress was applied for 40 minutes. A rapid response is a characteristic of SOD gene expression in A. acidoterrestris under heat and acid stresses, indicating that the SOD gene of A. acidoterrestris was closely related to the unique physiological mechanism for thermoacidophilic adaptation of A. acidoterrestris. © 2015, Editorial Board of Modern Food Science and Technology. All right reserved.