STRUCTURE OF CRYSTALLINE ALPHA-CHYMOTRYPSIN .5. ATOMIC STRUCTURE OF TOSYL-ALPHA-CHYMOTRYPSIN AT 2 A RESOLUTION
STRUCTURE OF CRYSTALLINE ALPHA-CHYMOTRYPSIN .5. ATOMIC STRUCTURE OF TOSYL-ALPHA-CHYMOTRYPSIN AT 2 A RESOLUTION
复制标题
DOI：
10.1016/0022-2836(72)90210-0
复制
发表时间：
1972-01-01
影响因子：
5.6
通讯作者：
BLOW, DM
中科院分区：
文献类型：
--
作者：
BIRKTOFT, JJ;BLOW, DM
通过对精心建立的原子模型的坐标进行计算精化，得到了甲苯磺酰-α-糜蛋白酶的原子坐标。从晶体学分析得到的分子的两个独立的视图几乎是相同的。从构象角、氢键网络和不同类型氨基酸侧链的环境等方面描述了酶的结构。多肽链折叠成两个氢键圆柱体，每个圆柱体包围一个疏水核心。许多溶剂分子可以被识别，包括13个埋在分子内部氢键圆柱体之间的分子。在酶的天然形式中观察到的结构差异被认为与活性中心的氢键有关。坐标给出的两个氨基酸（His 57和Ser 195），这是可测量的不同的天然form.The局部2倍轴相关的分子之间的相互作用进行了比较，在溶液中观察到的协会属性。
Refined atomic co-ordinates for tosyl-α-chymotrypsin have been obtained by computational refinement of co-ordinates derived from a carefully built atomic model. The two independent views of the molecule obtained from crystallographic analysis are almost identical. The structure of the enzyme is described in terms of conformational angles, hydrogen-bonding networks and the environment of different types of amino-acid side chain. The polypeptide chain is folded into two hydrogen-bonded cylinders, each enclosing a hydrophobic core. Many solvent molecules can be identified, including 13 buried between the hydrogen-bonded cylinders, inside the molecule.The structural differences observed in the native form of the enzyme are considered in relation to hydrogen bonds at the active centre. Co-ordinates are given for the two amino acids (His57 and Ser195) which are measurably different in the native form.The interactions between molecules related by local 2-fold axes are compared with the association properties observed in solution.