STRUCTURE STUDIES OF MOLECULAR CHAPERON HEAT SHOCK PROTEIN 40(HSP 40)

热休克蛋白70(Hsp70)家族的分子伴侣 结合未折叠的多肽底物以稳定或改变其 构象和水解三磷酸腺苷以促进多肽释放。这个 Hsp70的ATP水解酶受另一个蛋白伴侣的调节 家族热休克蛋白40(Hsp4O)(1)。据报道， Hsp4O可能与具有二级结构的多肽结合，相互作用 直接与Hsp70结合，并刺激Hsp70的ATP水解酶。Hsp4O 本身也可以结合变性多肽，并将它们重新折叠为 独立蛋白伴侣(2)。SIS I是Hsp4O蛋白的成员 酿酒酵母中的一个家族，是细胞所必需的 生存能力(3)。我们最近已经结晶了蛋白质Sis I， 晶体在SSRL站7-1衍射率为2.7A。我们建议解决 用MAD方法在BIOCARS第14站测定Sis I的晶体结构 BM-D。

Molecular chaperones of the Heat Shock Protein 70(Hsp7O) family bind unfolded polypeptide substrates to stabilize or alter their conformation and hydrolyze ATP to facilitate polypeptide release. The ATP hydrolysis of Hsp70 is regulated by another protein chaperon family Heat Shock Protein 40(Hsp4O)(1). It has been reported that Hsp4O may bind polypeptides with secondary structure, interact directly with Hsp70 and stimulate the ATP hydrolysis of Hsp70. Hsp4O itself can also bind denatured polypeptides and refold them as an independent protein chaperone(2). Sis I is a member of Hsp4O protein family in yeast Saccharomyces cerevisiae and it is essential for cell viability(3). We have crystallized the protein Sis I recently, the crystals diffract to 2.7A at SSRL station 7- 1. We propose to solve the crystal structure of Sis I by MAD method on BioCARS Station 14 BM-D.