芋螺毒素B179的化学合成及其氧化折叠的研究

Chemical synthesis and oxidative folding of conotoxin B179

目的合成新型芋螺毒素B179,并对其氧化折叠进行研究。方法采用Fmoc固相合成法合成芋螺毒素多肽B179,研究了不同的氧化缓冲液、谷胱甘肽浓度、还原型与氧化型谷胱甘肽的比例、以及温度对氧化折叠的影响。结果采用Fmoc固相合成法可以成功合成线性肽,其氧化折叠产物中主要为含一对二硫键的产物,但还出现了其他副产物,可能是含有分子间二硫键的折叠产物;在高浓度还原型谷胱甘肽环境下,折叠副产物更易形成;随着氧化反应温度升高,折叠反应速率加快。结论固相合成法可以有效合成芋螺毒素B179,且不同因素对其二硫键的形成有着较大的影响,本研究结果可为新型芋螺毒素的合成及其氧化折叠提供借鉴。

Objective To synthesize a novel contoxin B179 and investigate its chemical synthesis and oxidative folding.Methods Conotoxin B179 was synthesized by solid-phase synthesis method which contains a pair of disulfide bond.Various parameters affecting conotoxin B179 oxidative folding were optimized, which included different kinds of buffer,concentration and ratio of reduced and oxidized glutathione, and temperature.Results The linear conotoxin B179 can be synthesized successfully by Fmoc solid-phase synthesis.The conotoxin B179 oxidative products contained correct folded peptide with one pair of disulfide bond mainly.There was other by-product in the oxidative products,which might be the peptide mixture with the intermolecular disulfide bond.The folded by-product was increased with high concentration of reduced glutathione in the oxidative buffer.The conotoxin B179 oxidatvie folding reaction was speeded with higher temperature.Conclusion Conotoxin B179 could be synthesized effectively by Fmoc solid-phase synthesis method.There are some factors to impact the disulfide bond for- mation of conotoxin B179.The results would be the guidance for the synthesis of more novel conotoxins.