溴化1-辛基-3-甲基咪唑聚集状态对蛋白质结晶的影响研究  

Study on the effect of 1-octyl-3-methylimidazole bromide aggregation state on protein crystallization

作　　者：于筱溪 闫真真 蒋其辉 吴霞 张余晓 王晓娟 黄方[1,3] YU Xiaoxi;YAN Zhenzhen;JIANG Qihui;WU Xia;ZHANG Yuxiao;WANG Xiaojuan;HUANG Fang(College of Chemical Engineering,China University of Petroleum(East China),Qingdao 266580,Shandong,China;Downhole Operation Research Department,CNPC Engineering Technology R&D Company Limited,Beijing 102206,China;State Key Laboratory for Heavy Oil Processing,China University of Petroleum(East China),Qingdao 266580,Shandong,China)

机构地区：[1]中国石油大学(华东)化学工程学院,山东青岛266580 [2]中国石油集团工程技术研究院有限公司井下作业研究所,北京102206 [3]中国石油大学(华东)重质油国家重点实验室,山东青岛266580

出　　处：《化工学报》2021年第9期4854-4860,共7页CIESC Journal

基　　金：中国石油集团工程技术研究院有限公司开放课题(F2020185;CPET202016)。

摘　　要：研究了离子液体溴化1-辛基-3-甲基咪唑([C8mim]Br)添加剂的聚集状态对蛋白质结晶过程的影响。实验发现[C8mim]Br可以改善溶菌酶晶体形貌,影响晶体数量和晶体尺寸。通过测定不同浓度[C8mim]Br下溶菌酶的溶解度、结晶动力学、聚集状态和ζ-电势,揭示了离子液体[C8mim]Br对溶菌酶结晶的影响机理。结果表明,[C8mim]Br与溶菌酶的作用方式随[C8mim]Br的聚集状态而改变。当[C8mim]Br浓度较低(<0.1 mol/L)时,[C8mim]+与溶菌酶分子之间存在疏水作用,可以促进蛋白质分子聚集,促进结晶过程。当[C8mim]Br浓度较高(>0.1 mol/L)时,[C8mim]+自发聚集成胶束,并与蛋白质分子相互作用形成溶菌酶-胶束复合物;动态光散射(DLS)结果显示结晶过程以溶菌酶-胶束复合物为基本单元聚集,因此结晶过程减缓,晶体质量提高。The effect of the aggregation state of the ionic liquid 1-octyl-3-methylimidazole bromide([C8mim]Br)additives on the protein crystallization process was studied.Hen egg white lysozyme was chosen as the model protein and[C8mim]Br was applied as the additive.It was found that the presence of[C8mim]Br could improve the crystal morphology as well as affect the number and size of crystals.The influence mechanism of ionic liquid[C8mim]Br on the crystallization of lysozyme was revealed by measuring the solubility,crystallization kinetics,aggregation state and zeta-potential at different[C8mim]Br concentrations.The results showed that the interaction mechanism between lysozyme and[C8mim]Br varied with the aggregation states of[C8mim]Br.When the concentration of[C8mim]Br was low(<0.1 mol/L),there was hydrophobic interactions between[C8mim]+and lysozyme molecules,which promoted the aggregation and crystallization process.When the concentration of[C8mim]Br was high(>0.1 mol/L),[C8mim]+self-aggregated into micelle and formed aggregate complex with lysozyme molecules.The results from DLS further showed that the lysozyme-micelle complex was the basic unit in nucleation and hence,a slower crystallization rate and a higher crystal quality were obtained.

关 键 词：离子液体 聚集 蛋白质 结晶 

分 类 号：TQ423.9[化学工程]