Rigden Daniel J
School of Biological Sciences, University of Liverpool, Crown Street, Liverpool, UK.
FEBS Lett. 2009 May 19;583(10):1555-60. doi: 10.1016/j.febslet.2009.04.038. Epub 2009 May 3.
The Cry and Cyt classes of insecticidal toxins derived from the sporulating bacterium Bacillus thuringiensis are valuable substitutes for synthetic pesticides in agricultural contexts. Crystal structures and many biochemical data have provided insights into their molecular mechanisms, generally thought to involve oligomerization and pore formation, but have not localised the site on Cyt toxins responsible for selective binding of phospholipids containing unsaturated fatty acids. Here, distant homology between the structure of Cyt toxins and Erwinia virulence factor (Evf) is demonstrated which, along with sequence conservation analysis, allows a putative lipid binding site to be localised in the toxins.
源自产芽孢细菌苏云金芽孢杆菌的杀虫毒素Cry和Cyt类，在农业环境中是合成农药的宝贵替代品。晶体结构和许多生化数据为其分子机制提供了见解，一般认为该机制涉及寡聚化和孔形成，但尚未确定Cyt毒素上负责选择性结合含不饱和脂肪酸磷脂的位点。本文证明了Cyt毒素结构与欧文氏菌毒力因子（Evf）之间的远缘同源性，结合序列保守性分析，得以在毒素中定位一个假定的脂质结合位点。
