Ricin A-chain is an N-glycosidase that attacks ribosomal RNA at a highly conserved adenine residue. Crystallographic studies show that not only adenine and formycin, but also pterin-based rings can bind in the ricin active site. For a better understanding of the recognition mode between ricin, and adenine-like rings, the interaction energies and geometries were calculated for a number of complexes. Shiga toxin, a compound essentially identical to the protein originally isolated from Shigella dysenteniae, has an active protein chain that is a homologue of the ricin active chain, and catalyzes the same depurination reaction. The present invention is drawn to identifying inhibitors of ricin and Shiga toxin, using methods molecular mechanics and ab initio methods and using the identified inhibitors as antidotes to ricin or Shiga toxin, or to facilitate immunotoxin treatment by controlling non-specific cytotoxicity.
Ricin A-chain是一种N-糖基酶,它攻击高度保守的
腺嘌呤残基的
核糖体RNA。晶体学研究表明,不仅
腺嘌呤和福尔马霉素,而且基于黄素的环也可以结合在ricin活性位点上。为了更好地理解ricin和类
腺嘌呤环之间的识别模式,计算了许多复合物的相互作用能和几何结构。 Shiga毒素是一种化合物,其活性蛋白链与最初从志贺氏菌分离出的蛋白质基本相同,它催化相同的去
嘌呤反应。本发明旨在利用分子力学和从头算方法识别ricin和Shiga毒素的
抑制剂,并使用识别的
抑制剂作为ricin或Shiga毒素的解毒剂,或通过控制非特异性细胞毒性来促进免疫毒素治疗。