Conversion of a peroxiredoxin into a disulfide reductase by a triplet repeat expansion
Conversion of a peroxiredoxin into a disulfide reductase by a triplet repeat expansion
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DOI：
10.1126/science.1063143
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发表时间：
2001-10-05
期刊：
影响因子：
56.9
通讯作者：
Beckwith, J
中科院分区：
文献类型：
--
作者：
Ritz, D;Lim, J;Beckwith, J
还原蛋白质二硫键的途径存在于所有生物体中，并且是某些酶（包括必需蛋白质核糖核苷酸还原酶）的还原再循环所需的。缺乏硫氧还蛋白还原酶和谷胱甘肽还原酶的大肠杆菌菌株生长极差。在这里，我们表明，突变发生在高频率的基因ahpC，编码peroxiredoxin，恢复正常的增长，这种应变。这种突变是三联核苷酸重复序列可逆扩增的结果，导致添加一个氨基酸，将AhpC蛋白从过氧化物酶转化为二硫键还原酶。这两种活性之间的快速突变相互转换可能为E.杆菌
Pathways for the reduction of protein disulfide bonds are found in all organisms and are required for the reductive recycling of certain enzymes including the essential protein ribonucleotide reductase. An Escherichia coli strain that lacks both thioredoxin reductase and glutathione reductase grows extremely poorly. Here, we show that a mutation occurring at high frequencies in the gene ahpC, encoding a peroxiredoxin, restores normal growth to this strain. This mutation is the result of a reversible expansion of a triplet nucleotide repeat sequence, leading to the addition of one amino acid that converts the AhpC protein from a peroxidase to a disulfide reductase. The ready mutational interconversion between the two activities could provide an evolutionary advantage to E. coli.