Kalnov S L, Novikova L A, Zubatov A S, Luzikov V N
Biochem J. 1979 Jul 15;182(1):195-202. doi: 10.1042/bj1820195.
Degradation of mitochondrial translation products in Saccharomyces cerevisiae mitochondria was studied by selectively labelling these entities in vivo in the presence of cycloheximide and following their fate in isolated mitochondria. One-third to one-half of the mitochondrial translation products are shown to be degraded, depending on the culture growth phase, with an approximate half-life of 35 min. This process is shown to be ATP-dependent, enhanced in the presence of puromycin and inhibited by chloramphenicol. Further, the proteolysis is suppressed by detergents and is insensitive to antisera against yeast proteinases A and B when measured in mitochondria or 'inside-out' submitochondrial particles. It is concluded that the breakdown of mitochondrial translation products is most probably due to the action of endogenous proteinase(s) associated with the mitochondrial inner membrane. This proteinase is inhibited by phenylmethanesulphonyl fluoride, leupeptin, antipain and chymostatin.
通过在环己酰亚胺存在的情况下体内选择性标记酿酒酵母线粒体中的翻译产物,并追踪其在分离线粒体中的命运,对线粒体翻译产物的降解进行了研究。结果表明,根据培养生长阶段,三分之一到二分之一的线粒体翻译产物会被降解,其半衰期约为35分钟。该过程显示为ATP依赖性,在嘌呤霉素存在下增强,而被氯霉素抑制。此外,当在线粒体或“外翻”亚线粒体颗粒中测量时,蛋白水解被去污剂抑制,并且对针对酵母蛋白酶A和B的抗血清不敏感。得出的结论是,线粒体翻译产物的分解很可能是由于与线粒体内膜相关的内源性蛋白酶的作用。这种蛋白酶被苯甲基磺酰氟、亮抑酶肽、抗蛋白酶和抑肽酶抑制。