Gould A R, Mabbutt B C, Norton R S
School of Biochemistry, University of New South Wales, Kensington, Australia.
Eur J Biochem. 1990 Apr 20;189(1):145-53. doi: 10.1111/j.1432-1033.1990.tb15471.x.
Selective proteolysis of the polypeptide cardiostimulant anthopleurin-A by trypsin introduces a single break in the polypeptide backbone on the C-terminal side of Arg14. The resulting derivative is devoid of any cardiostimulant activity. The structural changes which accompany this loss of activity have been examined by one- and two-dimensional 1H-NMR spectroscopy. It is shown that the overall backbone folding of anthopleurin-A is conserved on digestion, with some structural changes occurring for residues which are adjacent to the site of cleavage by trypsin. Thus, although previous NMR studies on anthopleurin-A indicate that the region surrounding Arg14 is devoid of any ordered structure, it appears that some degree of structural integrity is required to allow the essential side chains to adopt the conformation necessary to produce a cardiostimulant effect.
用胰蛋白酶对多肽强心剂海葵毒素-A进行选择性蛋白水解，会在多肽主链上精氨酸14的C端一侧产生一个单一断裂点。所得衍生物没有任何强心剂活性。通过一维和二维1H-NMR光谱研究了伴随这种活性丧失的结构变化。结果表明，海葵毒素-A的整体主链折叠在消化过程中得以保留，胰蛋白酶切割位点附近的残基发生了一些结构变化。因此，尽管之前对海葵毒素-A的NMR研究表明精氨酸14周围区域没有任何有序结构，但似乎需要一定程度的结构完整性，以使必需的侧链能够采取产生强心剂效应所需的构象。
