Pedone Emilia, Limauro Danila, D'Alterio Romina, Rossi Mosè, Bartolucci Simonetta
Istituto di Biostrutture e Bioimmagini, C.N.R., Naples, Italy.
FEBS J. 2006 Dec;273(23):5407-20. doi: 10.1111/j.1742-4658.2006.05533.x. Epub 2006 Oct 31.
A potential role in disulfide bond formation in the intracellular proteins of thermophilic organisms has recently been ascribed to a new family of protein disulfide oxidoreductases (PDOs). We report on the characterization of SsPDO, isolated from the hyperthermophilic archaeon Sulfolobus solfataricus. SsPDO was cloned and expressed in Escherichia coli. We revealed that SsPDO is the substrate of a thioredoxin reductase in S. solfataricus (K(M) 0.3 microm) and not thioredoxins (TrxA1 and TrxA2). SsPDO/S. solfataricus thioredoxin reductase constitute a new thioredoxin system in aerobic thermophilic archaea. While redox (reductase, oxidative and isomerase) activities of SsPDO point to its central role in the biochemistry of cytoplasmic disulfide bonds, chaperone activities also on an endogenous substrate suggest a potential role in the stabilization of intracellular proteins. Northern and western analysis have been performed in order to analyze the response to the oxidative stress.
最近，一个新的蛋白质二硫键氧化还原酶（PDO）家族被认为在嗜热生物的细胞内蛋白质二硫键形成中发挥潜在作用。我们报告了从嗜热古菌嗜热栖热菌中分离出的SsPDO的特性。SsPDO在大肠杆菌中克隆并表达。我们发现SsPDO是嗜热栖热菌中硫氧还蛋白还原酶的底物（K(M)为0.3微摩尔），而不是硫氧还蛋白（TrxA1和TrxA2）。SsPDO/嗜热栖热菌硫氧还蛋白还原酶在需氧嗜热古菌中构成了一个新的硫氧还蛋白系统。虽然SsPDO的氧化还原（还原酶、氧化和异构酶）活性表明其在细胞质二硫键生物化学中起核心作用，但对一种内源性底物的伴侣活性表明其在细胞内蛋白质稳定方面具有潜在作用。为了分析对氧化应激的反应，我们进行了Northern和western分析。
