杀虫晶体蛋白的序列特征与其杀小菜蛾活性间关系的定量模型.pdfVIP

生 物 工 程 学 报 Chin J Biotech 2008, August 25; 24 8 : 1395-1400 Chinese Journal of Biotechnology ISSN 1000-3061 cjb@ ? 2008 Institute of Microbiology, CAS CSM, All rights reserved 研究报告 杀虫晶体蛋白的序列特征与其杀小菜蛾活性间关系的定 量模型 林毅, 蔡福营, 张光亚 华侨大学生物工程与技术系 工业生物技术福建省高校重点实验室, 泉州 362021 摘 要: 采用定点突变技术改造杀虫晶体蛋白, 是提高其杀虫活性的有效途径, 但目前在突变位点和氨基酸种类的选 取上还存在很大的盲目性。以杀小菜蛾活性明确的23 个杀虫晶体蛋白上的4 个关键结构域为研究对象, 用主成分分析 法处理20 种氨基酸 1369 种性质参数后的第一个主成分的得分向量来表征氨基酸差异, 实现序列数据化。通过逐步回归 找到了6 个关键氨基酸位点: X 、X 、X 、X 、X 和X , 并进一步通过偏最小二乘二次多项式回归寻根最优氨基酸 3 9 12 13 14 19 残基L/X3 、S/X9 、S/X12、T/X13 、A/X14 和G/X19, 从而建立了杀虫晶体蛋白的序列特征与其杀小菜蛾活性间关系的 定量模型。这有助于快速地预测出有利于提高杀小菜蛾活性的氨基酸位点和种类, 从而提高定点突变改造杀虫晶体蛋白 的效率。 关键词: 杀虫晶体蛋白, 小菜蛾, 序列特征, 定量模型, 理性设计 Modeling Relationship between Sequence Characteristics of Insecticidal Crystal Proteins and Their Inhibitory against Plutella xylostella Yi Lin, Fuying Cai, and Guangya Zhang Department of Bioengineering Biotechnology, Huaqiao University, Quanzhou 362021, China Abstract: The knowledge of the relationship between sequence characteristics of insecticidal crystal proteins ICP and their inhibitory against Plutella xylostella provided helpful information for the rational design of ICP with desirable activity against Plutella xylostella.The four key loops of ICP with determined activities against Plutella xylostella were selected to study the quantitative relationship between sequence characteristics and insecticidal activity. The first principle components’ score vectors for 20 amino acids were assigned to converting amino acids into data. The six key sites X , X , X , X , X and X were predicted by 3 9 12 13 14 19 stepwise regression method. The amino acids L/ X , S/ X , S/ X , T/ X , A/ X and G/ X found by partial least squares regression 3 9 12 13 14 19 and second order polynomial models were predicted to increase the activity of ICP against Plutel