晶体细化和原子模型的人类Fc片段及其复杂的蛋白质片段B从金黄色葡萄球菌在2.9 - 2.8 a分辨率。
文章的细节
-
引用
复制到剪贴板 -
Deisenhofer J
晶体细化和原子模型的人类Fc片段及其复杂的蛋白质片段B从金黄色葡萄球菌在2.9 - 2.8 a分辨率。
生物化学。1981年4月28日,20 (9):2361 - 70。
- PubMed ID
-
7236608 (在PubMed]
- 文摘
-
人类Fc的模型片段被精炼为2.9 a分辨率。使用了两种不同的自动程序晶体细化(Deisenhofer, J。& Steigemann w (1975) Acta Crystallogr。,秒。B B31, 238;杰克,一个。和莱维特,m (1978) Acta Crystallogr。教派。A34, 931]。最后的R值是0.22。甲基域相似的二聚体CH1-CL总在Fab片段。之间没有联系CH2域。CH2和CH3域之间的联系已经大约三分之一的大小CH3-CH3接触。碳水化合物,支链的九个己糖单位,覆盖部分C-contact CH2域,屏蔽此表面的疏水残基。六个原子内碳水化合物的氢键的原子距离CH2域。 Crystallographic refinement of the complex between Fc fragment and fragment B of protein A from Staphylococcus aureus reduced the R value of the model is 0.24. A major part of the structure of fragment B consists of two alpha helics; the rest of the polypeptide chain is folded irregularly. In the crystal, fragment B forms two contacts with Fc fragment molecules. Contact 1 involves residues from both helices of fragment B, and residues from the CH2 and CH3 domains of FC, and is predominantly hydrophobic. Contact 2 is smaller than contact 1. Residues from the second helix and adjacent residues of fragment B and residues only from the CH3 domain of Fc contribute to contact 2. The nature of contact 2 is mainly polar and includes a sulfate ion. There are strong arguments that contact 1 is the fragment B-Fc contact formed in solution under physiological conditions, while contact 2 is a crystal contact.