摘要
虎纹捕鸟蛛毒素 Ⅰ (Huwentoxin Ⅰ ,HWTX Ⅰ )是从虎纹捕鸟蛛 (Selenocosmiahuwena)的粗毒中分离出的一种多肽类神经毒素。为了探明该毒素分子中唯一的Arg残基与其生物学活性的关系 ,运用固相多肽合成技术和Fmoc化学直接构建了Ala取代HWTX Ⅰ第 2 0位Arg(R2 0 )的突变体R2 0A HWTX Ⅰ ;将合成的突变体置于含谷胱甘肽的缓冲体系中氧化复性后用反相和特殊设计的离子交换HPLC纯化 ,并对之进行氨基酸组成、Edman降解与质谱分析。活性测定结果表明 ,HWTX Ⅰ分子中的R2 0被A取代后 ,活性下降了 92 % ,提示R2 0是与活性密切相关的重要残基。
Huwentoxin\|Ⅰ(HWTX Ⅰ) is a polypeptide neurotoxin purified from the venom of the spider Selenocosmia huwena. R20A\|HWTX\|Ⅰ,a mutant of HWTX Ⅰ in which the Arg was replaced by Ala,was synthesized on solid support by using Fmoc chemistry.The synthetic mutant was oxdatively renatured in glutathione\|containing buffer,and then isolated by reversed phase and specially designed ion\|exchange HPLC.The chemical structure of R20A\|HWTX\|Ⅰ was confirmed by amino acid analysis,Edman degradation and MALDI\|TOF mass analysis.Physiological experiment showed that the replacement of R20 by a decreased the bioactivity of the HWTX Ⅰ by 92%,indicating that R20 is a key residue closely related to the bioactivity of the HWTX Ⅰ.
出处
《生物工程学报》
CAS
CSCD
北大核心
2000年第4期490-494,共5页
Chinese Journal of Biotechnology
基金
国家高技术研究发展计划项目!( 10 3 13 0 1 0 6)
关键词
虎纹捕鸟蛛毒素-Ⅰ
突变体
蛋白质工程
化学合成
Huwentoxin\|Ⅰ
mutant
solid phase peptide synthesis
protein engineering
spider
