摘要
综述了酵母乙酰乳酸合成酶(ScALS)与磺酰脲类除草剂氯嘧磺隆(chlorimuron-ethyl,CE)形成的复合物在0.28nm分辨率下的晶体结构及拟南芥乙酰乳酸合成酶(AtALS)与磺酰脲类和咪唑啉酮类除草剂复合物的三维结构。除草剂的分子结构与酶、底物并不相似,但它们与酶形成的复合物可阻断底物进入酶活性位点通路而起抑制作用。连接磺酰脲的10个氨基酸残基同样连接咪唑喹啉酸,另有6个残基只与磺酰脲而不与咪唑喹啉酸相连,有2个残基只与咪唑喹啉酸而不与磺酰脲相连,即两种抑制剂占据了特别的重叠位点,但以不同方式连接。抗性杂草的产生是因为突变株ALS的残基位点变异,从而引起除草剂与ALS结合方式的变化。这些研究对进一步理解除草剂与靶分子的作用方式及除草剂的分子药物设计具有重要的指导作用。
The 0.28 nm resolution crystal structure of yeast acetolactate synthase in complex with a sulfonylurea herbicide, chlorimuron ethyl and the 3D structure of Arabidopsis thaliana acetolactate synthase in complex with sulfonylureas and imidazolinone herbicides were reviewed. Neither class of these molecules has a structure that may mimic the substrates for the enzyme, they act by blocking a channel of the ALS through which access to the active site. Ten of the amino acid residues that bind the sulfonylureas can also bind with imazaquin （IQ）. Six additional residues interact only with the sulfonylureas, whereas there were two residues that bind IQ but not the sulfonylureas. The mutation of ALS residue sites causes the appearance of resistant weed, and it also changes the binding mode between herbicide and ALS, Research advances on the 3D structure of ALS is important to discover molecular mechanism of mutation of the weed and for the rational design of further herbicidal compounds.
出处
《农药学学报》
CAS
CSCD
2007年第1期6-13,共8页
Chinese Journal of Pesticide Science
基金
国家重点基础研究发展计划("973"计划)资助项目(2003CB114400)
作者简介
姜玲（1982-），女，博士研究生，主要从事生物化学与分子生物学方面的研究；
通讯作者：向文胜（1968-），男，土家族，教授，主要从事农药生物化学方面的研究．联系电话：0451-55190413；E-mall：xiangwensheng@yahoo．com．cn
