一种反平行螺旋多肽的自组装结构研究  

Study on the self-assembling structure of an antiparallel-helical peptide

作　　者：林娟[1] 廖戎[2] 万静[2] 杨胜韬[2] 石治川[2] 罗建斌[2] 周庆翰[2] 

机构地区：[1]成都医学院生物医学系,四川成都610500 [2]西南民族大学化学与环境保护工程学院,四川成都610041

出　　处：《化学研究与应用》2013年第8期1149-1154,共6页Chemical Research and Application

基　　金：四川省教育厅科研基金项目(10ZC091)资助;成都医学院自然科学基金项目(CYZ11-010)资助;西南民族大学2013年国家外专项目(2013-35)资助;西南民族大学省级大学生创新创业训练计划项目(S201310656083)资助

摘　　要：自然界中广泛存在着天然蛋白质的自组装行为,而多肽的自组装研究近年来已成为纳米科学以及生物医学研究的一个热点。本研究中将氨基酸序列(GAGA)与离子互补型多肽RADA16-I序列进行部分替换,设计了双亲性多肽RAGA16。采用原子力显微镜(AFM)、透射电子显微镜(TEM)、圆二色谱(CD)等技术对多肽RADA16-I、RAGA16的自组装行为、肽链的二级结构进行了表征。结果表明,RAGA16在水溶液中形成纳米纤维结构,其在自组装过程中由无规卷曲结构转变为β-折叠结构。进一步研究发现,与RADA16-I的自组装模不同,RAGA16纳米纤维采取一种稳定的反平行螺旋自组装结构。最后,本文对RAGA16的自组装模式进行了推测,并对两种多肽的自组装模式进行了对比。Due to the abundant protein self-assemblies existing in nature,recently,the self-assembly of peptides had gained much focus in nanoscience and biomedicine.A novel amphiphilic peptide,RAGA16,was designed by partially replacing GAGA sequence with an ionic self-complementary peptide RADA16-I.Modern analysis methods were utilized to study the self-assembly behavior and the secondary structure of two peptides by atomic force microscopy（AFM）,transmission electron microscopy（TEM）,and circular dichroism（CD）assessment.By the experimental results,RAGA16 formed a nano-fiber structure in water,and a dramatic conformational transition from random-coil to β-sheet happed during the self-assembling process.Further research revealed that RAGA16 formed a stable antiparallel helical structure,which was different from the self-assembly mechanism of RADA16-I.Finally,compared with RADA16-I the self-assembly mechanism of RAGA16 was proposed.

关 键 词：多肽 自组装 反平行螺旋结构 构象转变 

分 类 号：Q518.1[生物学—生物化学]