尿毒症毒素多肽二级结构的测定和预测  

Determination and Forecast of Secondary Structure of Uremic Toxic Polypeptide

作　　者：李国华 李纪红[1] 杨眉[1] 王蔚[1] 孙平川[1] 袁直[1] 

机构地区：[1]南开大学高分子化学研究所

出　　处：《高等学校化学学报》2005年第10期1855-1857,共3页Chemical Journal of Chinese Universities

基　　金：国家"九七三"计划项目(批准号:G1999064707);国家自然科学基金(批准号:59873011)资助.

摘　　要：A uremic toxic compound with molecular weight 1007.94 was determined to be an octapeptide by mass spectrometry.Its amino-acid sequence was given as follos: Val-Val-Arg-Gly-Cys-Thr-Trp-Trp.Spin systems for amino acid residues in the octapeptide were identified through analysis of 2D NMR 1H-1H DQF-COSY,TOCSY and ROESY spectra acquired in H2O and D2O.Moreover,the complete assignment of proton resonances for the backbone and side chain was achieved.Based on the secondary chemical shift（Δδ） of the residues,the secondary structure of octapeptide was surveyed.Conformational analyses according to Chemical Shift Index（CSI） showed that the secondary structure of the octapeptide was principally α-helix.The CD spectra of the peptide in aqueous solution gave the same result.Additions of linear polymers made the conformations of octapeptide stretch.These experimental results provide a basis for further comprehension of interaction regulation between biomacromolecule and polymer absorbing materials.A uremic toxic compound with molecular weight 1007.94 was determined to be an octapeptide by mass spectrometry. Its amino-acid sequence was given as folios： Val-Val-Arg-Gly-Cys-Thr-Trp-Trp. Spin,systems for amino acid residues in the octapeptide were identified through analysis of 2D NMR ^1H-^1 H DQF-COSY, TOCSY and ROESY spectra acquired in H2O and D2O. Moreover, the complete assignment of proton resonances for the backbone and side chain was achieved. Based on the secondary chemical shift（△δ） of the residues, the secondary structure of octapeptide was surveyed. Conformational analyses according to Chemical Shift Index（CSI） showed that the secondary structure of the octapeptide was principally α-helix. The CD spectra of the peptide in aqueous solution gave the same result. Additions of linear polymers made the conformations of oetapeptide stretch. These experimental results provide a basis for further comprehension of interaction regulation between biomacromolecule and polymer absorbing materials.

关 键 词：尿毒症毒素多肽 次级化学位移 线性聚合物 

分 类 号：O629[理学—有机化学] Q592.1[理学—化学]