Sackmann U, Zensen R, Röhlen D, Jahnke U, Weiss H
Institut für Biochemie, Universität Düsseldorf, Federal Republic of Germany.
Eur J Biochem. 1991 Sep 1;200(2):463-9. doi: 10.1111/j.1432-1033.1991.tb16205.x.
We determined the primary structure of a 9.6-kDa subunit of the respiratory chain NADH:ubiquinone reductase (complex I) from Neurospora crassa mitochondria and found a close relationship between this subunit and the bacterial or chloroplast acyl-carrier protein. The degree of sequence identity amounts to 80% in a region of 19 residues around the serine to which the phosphopantetheine is bound. The N-terminal presequence of the subunit has the characteristic features of a mitochondrial import sequence. We cultivated the auxotroph pan-2 mutant of N. crassa in the presence of [14C]pantothenate and recovered all radioactivity incorporated into mitochondrial protein in the 9.6-kDa subunit of complex I. We cultivated N. crassa in the presence of chloramphenicol to accumulate the nuclear-encoded peripheral arm of complex I. This pre-assembled arm also contains the 9.6-kDa subunit. These results demonstrate that an acyl-carrier protein with pantothenate as prosthetic group is a constituent part of complex I in N. crassa.
我们确定了来自粗糙脉孢菌线粒体的呼吸链NADH：泛醌还原酶（复合体I）9.6 kDa亚基的一级结构，发现该亚基与细菌或叶绿体酰基载体蛋白之间存在密切关系。在与磷酸泛酰巯基乙胺结合的丝氨酸周围19个残基的区域中，序列同一性程度达80%。该亚基的N端前序列具有线粒体导入序列的特征。我们在[14C]泛酸盐存在的情况下培养粗糙脉孢菌的营养缺陷型pan - 2突变体，并在复合体I的9.6 kDa亚基中回收了所有掺入线粒体蛋白的放射性。我们在氯霉素存在的情况下培养粗糙脉孢菌，以积累复合体I的核编码外周臂。这个预组装的臂也包含9.6 kDa亚基。这些结果表明，以泛酸盐作为辅基的酰基载体蛋白是粗糙脉孢菌中复合体I的组成部分。
