Gooley P R, Norton R S
Eur J Biochem. 1985 Dec 16;153(3):529-39. doi: 10.1111/j.1432-1033.1985.tb09334.x.
The specific assignment of resonances in the 300-MHz 1H nuclear magnetic resonance (NMR) spectrum of anthopleurin-A, a polypeptide cardiac stimulant from the sea anemone Anthopleura xanthogrammica, is described. Assignments have been made using two-dimensional NMR techniques, in particular the method of sequential assignments, where through-bond and through-space connectivities to the peptide backbone NH resonances are used to identify the spin systems of residues adjacent in the amino acid sequence. Complete assignments have been made of the resonances from 33 residues out of a total of 49, and partial assignments of a further 3. The resonances from several of the remaining residues have been identified but not yet specifically assigned. A complicating factor in making these assignments is the conformational heterogeneity exhibited by anthopleurin-A in solution. The resonances from a number of amino acid residues in the minor conformer have also been assigned. These assignments contribute towards identification of the origin of this heterogeneity, and permit some preliminary conclusions to be drawn regarding the secondary structure of the polypeptide.
本文描述了从黄海葵（Anthopleura xanthogrammica）中提取的多肽类心脏兴奋剂海葵素A（anthopleurin-A）在300兆赫氢核磁共振（NMR）谱中的共振峰具体归属。归属是利用二维NMR技术完成的，特别是序列归属方法，即通过与肽主链NH共振的键连和空间连接来确定氨基酸序列中相邻残基的自旋系统。总共49个残基中，已完成了33个残基共振峰的完全归属，另有3个残基的部分归属。其余几个残基的共振峰已被识别，但尚未具体归属。进行这些归属时的一个复杂因素是海葵素A在溶液中呈现的构象异质性。次要构象中一些氨基酸残基的共振峰也已被归属。这些归属有助于确定这种异质性的来源，并能就该多肽的二级结构得出一些初步结论。
