Discovery of an intermolecular disulfide bond required for the thermostability of a heterodimeric protein from the thermophile Hydrogenobacter thermophilus
Discovery of an intermolecular disulfide bond required for the thermostability of a heterodimeric protein from the thermophile Hydrogenobacter thermophilus
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发现嗜热嗜热氢杆菌异二聚体蛋白热稳定性所需的分子间二硫键
DOI：
10.1080/09168451.2015.1079476
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
and Masaharu Ishii
中科院分区：
文献类型：
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作者：
Keug Tae Kim;Yoko Chiba;Hiroyuki Arai;and Masaharu Ishii
提高蛋白质热稳定性的因素在科学和工业领域都具有相当大的兴趣。二硫键是增加热稳定性的因素之一，但由于胞质溶胶的还原环境，在细胞内蛋白质中很少发现。在这里，我们报告的第一个例子的异源亚基的一种新型的磷酸丝氨酸磷酸酶从嗜热菌Hydrogenophilus，这有助于蛋白质的热稳定性在生理温度下的异源亚基之间的分子间二硫键。使用SDS-PAGE比较野生型和半胱氨酸缺失突变体之间剩余的可溶性蛋白质显示，二硫键通过将具有低溶解度的亚基紧密连接到具有较高溶解度的伴侣来增加整个蛋白质的热稳定性。此外，还强烈表明二硫键的形成有助于体内稳定性。这一发现将为设计具有更高热稳定性的蛋白质开辟新的途径。
Factors that increase protein thermostability are of considerable interest in both scientific and industrial fields. Disulfide bonds are one of such factors that increase thermostability, but are rarely found in intracellular proteins because of the reducing environment of the cytosol. Here, we report the first example of an intermolecular disulfide bond between heteromeric subunits of a novel-type phosphoserine phosphatase from a thermophilic bacteriumHydrogenobacter thermophilus, which contributes to the protein thermostability at the physiological temperature. Comparison of remaining soluble proteins between wild-type and cysteine-deleted mutant using SDS-PAGE revealed that the disulfide bond increases the thermostability of the whole protein by tightly connecting a subunit with low solubility to the partner with higher solubility. Furthermore, it was strongly suggested that the disulfide bond is formed and contributes to the stabilityin vivo. This finding will open new avenues for the design of proteins with increased thermostability.