分离的蓖麻毒素A链和B链的圆二色性

Circular dichroism of isolated ricin A- and B-chains.

作者信息

Wawrzynczak E J, Drake A F, Thorpe P E

机构信息

Drug Targeting Laboratory, Imperial Cancer Research Fund Laboratories, London, U.K.

出版信息

Biophys Chem. 1988 Sep;31(3):301-5. doi: 10.1016/0301-4622(88)80036-x.

DOI:10.1016/0301-4622(88)80036-x

PMID:3233304

Abstract

An analysis of the circular dichroism (CD) spectra of isolated ricin A- and B-chains revealed several bands not apparent in the spectrum of intact ricin. Arithmetic combination of the A- and B-chain spectra gave a composite spectrum resembling that of native ricin, indicating that the two chains did not undergo any major conformational change upon dissociation. The addition of lactose to the B-chain at pH 7.2 caused a slight perturbation of a tryptophan-derived negative CD band centred at 283 nm without change to the overall structure of the polypeptide.

摘要

对分离出的蓖麻毒素A链和B链的圆二色性（CD）光谱分析显示，完整蓖麻毒素光谱中不明显的几条谱带。A链和B链光谱的算术组合得到了一个类似于天然蓖麻毒素的复合光谱，这表明两条链在解离时没有发生任何重大构象变化。在pH 7.2条件下向B链中添加乳糖，会使以283 nm为中心的色氨酸衍生的负CD谱带略有扰动，而多肽的整体结构没有变化。