2 CONFORMATIONS OF CRYSTALLINE ADENYLATE KINASE
2 CONFORMATIONS OF CRYSTALLINE ADENYLATE KINASE
复制标题
DOI：
10.1016/0022-2836(77)90280-7
复制
发表时间：
1977-01-01
影响因子：
5.6
通讯作者：
SCHULZ, GE
中科院分区：
文献类型：
--
作者：
SACHSENHEIMER, W;SCHULZ, GE
猪肌肉腺苷酸激酶（EC 2.7.4.3）有3种晶型，它们可以相互转化。对于晶型A，酶结构在原子细节上是已知的。晶型B在4.7埃的X射线衍射分析。报告了分离度并与A型进行了比较。在从A到B的转变过程中，分子的堆积排列略有变化。单个分子经历了可感知的构象变化：通过置换7个残基的链段和2个相邻的α-在螺旋中，疏水口袋在靠近分子中心的裂缝深处打开。伴随着β-折叠片材以B形式增大了约4个氢键。一些证据表明，观察到的构象变化是分子的内在性质，而不是由晶体堆积力引起的。
Pig muscle adenylate kinase (EC 2.7.4.3) can exist in 3 crystal forms, which are interconvertible. For crystal form A the enzyme structure was known in atomic detail. The X-ray diffraction analysis of crystal form B at 4.7 .ANG. resolution and a comparison with the A form was reported. During the transition from A to B the packing arrangement of the molecules changed slightly. The individual molecule underwent an appreciable conformational change: by displacing a chain segment of 7 residues and 2 adjacent .alpha.-helices a hydrophobic pocket was opened deep in the cleft near the center of the molecule. Concomitantly the .beta.-pleated sheet was enlarged by about 4 hydrogen bonds in the B form. Several lines of evidence indicated that the observed conformational change was an intrinsic property of the molecule and was not induced by crystal packing forces.