SOLUTION CONFORMATION OF PROTEINASE INHIBITOR-IIA FROM BULL SEMINAL PLASMA BY H-1 NUCLEAR MAGNETIC-RESONANCE AND DISTANCE GEOMETRY
SOLUTION CONFORMATION OF PROTEINASE INHIBITOR-IIA FROM BULL SEMINAL PLASMA BY H-1 NUCLEAR MAGNETIC-RESONANCE AND DISTANCE GEOMETRY
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DOI：
10.1016/0022-2836(85)90347-x
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发表时间：
1985-01-01
影响因子：
5.6
通讯作者：
WUTHRICH, K
中科院分区：
文献类型：
--
作者：
WILLIAMSON, MP;HAVEL, TF;WUTHRICH, K
A determination of the solution of the solution conformation proteinase inhibitor IIA from bull seminal plasma (BUSI IIA) is described. Two-dimensional nuclear Overhauser enhancement spectroscopy (NOESY) was used to obtain a list of 202 distance constraints between individually assigned H atoms of the polypeptide chain, to identify the positions of the 3 disulfide bridges, and to locate the single cis peptide bond. Supplementary geometric constraints were derived from the vicinal spin-spin couplings and the locations of certain H bonds, as determined by NMR. Using a new distance geometry program (DISGEO) which is capable of computing all-atom structures for proteins the size of BUSI IIA, 5 conformers were computed from the NOE distance constraints alone, and another five were computed with the supplementary constraints included. Comparison of the different structures computed from the NMR data among themselves and with the crystal structures of 2 homologous proteins shows that the global features of the conformation of BUSI IIA (i.e., the overall dimensions of the molecule and the threading of the polypeptide chain) were well-defined by the available NMR data. A preliminary energy refinement of the structure is described, which showed that the constraints derived from the NMR data are compatible with a low energy spatial structure.
