Bex F, Sels A A
Biochimie. 1977;59(1):79-84. doi: 10.1016/s0300-9084(77)80089-8.
A mutant of Saccharomyces cerevisiae, unable to grow at the expense of non fermentable carbon sources at 37 degrees C, has been selected; at 25 degrees C the mutant strain behaves like the parental wild strain. Evaluations of respiration rates during aerobic growth at restrictive temperature on one hand, enzymatic and/or spectral evaluations of the individual components of the respiratory chain on the other hand show that the respiratory deficiency is specifically correlated with a reduced level of cytochrome oxidase. The decrease of enzyme activity is the direct consequence of a lowering of hemoprotein (a,a3) concentration. Temperature-activity relationship of cytochrome oxidase elaborated at the permissive temperature by the mutant strain is modified as far as the particulate enzyme is concerned, but no difference is observed after partial solubilization of the enzyme by non ionic surfactant. Genetic analysis shows that the mutant phenotype results from a nuclear gene mutation.
已筛选出一种酿酒酵母突变体，该突变体在37℃下无法利用非发酵性碳源生长；在25℃时，突变菌株的行为与亲本野生菌株相似。一方面，在限制温度下对需氧生长期间的呼吸速率进行评估，另一方面，对呼吸链各个组分进行酶学和/或光谱评估，结果表明呼吸缺陷与细胞色素氧化酶水平降低存在特定关联。酶活性的降低是血蛋白（a,a3）浓度降低的直接结果。就颗粒酶而言，突变菌株在允许温度下产生的细胞色素氧化酶的温度-活性关系发生了改变，但在用非离子表面活性剂对酶进行部分溶解后未观察到差异。遗传分析表明，突变表型是由核基因突变引起的。
