超氧化物歧化酶在酿酒酵母碱胁迫抗性中的功能研究

Effect of Superoxide Dismutase on Alkaline Stress Resistance of Saccharomyces cerevisiae

[目的]研究酿酒酵母超氧化物歧化酶与其碱胁迫抗性的相关性。[方法]采用可见分光光度法,测定碱胁迫条件下酵母菌超氧化物歧化酶活性(SOD)指标;采用平板滴定生长试验,检测酿酒酵母铜/锌超氧化物歧化酶缺失菌株(sod1Δ)和锰超氧化物歧化酶缺失菌株(sod2Δ)的碱胁迫抗性;采用台盼蓝染色,检测碱胁迫条件下酵母细胞的存活率。[结果]在pH值为7.9条件下处理2h可明显诱导酵母细胞内SOD活性升高;与野生型酵母菌株相比,sod1Δ和sod2Δ基因缺失菌均表现碱胁迫敏感表型,并且碱胁迫条件下细胞存活率明显下降。[结论]超氧化物歧化酶在调控酿酒酵母碱胁迫抗性中发挥重要作用。

[Objective] The research aimed to investigate the possible role of superoxide dismutase in the resistance to alkaline stress in Saccharomyces cerevisiae.[Method] Under alkaline stress condition,the activity of superoxide dismutase was measured by means of visible spectrophotometry,and the yeast cell viability was determined by trypan blue staining.The sensitivities of sod1Δ and sod2Δ mutants to alkaline stress resistance were tested by the spot-plate growth assay.[Result] After 2h exposure at pH 7.9,the superoxide dismutase activity increased in yeast under alkaline stress condition.Both sod1Δ and sod2Δ showed increased sensitivity to alkaline stress and the significant decreases of cell viability,compared with the wild type yeast strain.[Conclusion] The super-oxide dismutase is essential for the tolerance to alkaline stress in Saccharomyces cerevisiae.