Odd-Even Sequence Effect of Surface-Mediated Peptide Assemblies Observed by Scanning Tunneling Microscopy  

作　　者：郭元元 王晨轩 侯静菲 杨爱华 张雪梅 王宜冰 张敏 杨延莲 王琛 

机构地区：[1]National Center for Nanoseience and Technology,Beoing 100190,China

出　　处：《Chinese Journal of Chemistry》2012年第9期1987-1991,共5页中国化学（英文版）

摘　　要：The peptide assembly structures of polyglutamine （PolyQ） have been studied by using scanning tunneling microscopy （STM） with high spatial resolution in ambient conditions. 4,4＇-Bipyridyl （4Bpy） was introduced into the PolyQ7 and PolyQ8 peptide assemblies for labeling the C-termini of the peptides. The fine structures of the 4Bpy-PolyQ7 and 4Bpy-PolyQ8 co-assemblies are observed, and the statistics of the apparent peptide strand length reveal different length distributions for PolyQ7 and PolyQs. One predominant apparent peptide strand length is ob- served for PolyQ7 reflecting one predominant peptide conformation in assembly structures, while three major ap- parent strand lengths can be identified with PolyQ8 reflecting three co-existing peptide conformations in peptide as- semblies. Such drastic difference in assembling characteristics can be considered as a reflection of asymmetric ad- sorption effect ofpeptides relating to odd-even residue numbers of PolyQ7 and PolyQ8,The peptide assembly structures of polyglutamine （PolyQ） have been studied by using scanning tunneling microscopy （STM） with high spatial resolution in ambient conditions. 4,4＇-Bipyridyl （4Bpy） was introduced into the PolyQ7 and PolyQ8 peptide assemblies for labeling the C-termini of the peptides. The fine structures of the 4Bpy-PolyQ7 and 4Bpy-PolyQ8 co-assemblies are observed, and the statistics of the apparent peptide strand length reveal different length distributions for PolyQ7 and PolyQs. One predominant apparent peptide strand length is ob- served for PolyQ7 reflecting one predominant peptide conformation in assembly structures, while three major ap- parent strand lengths can be identified with PolyQ8 reflecting three co-existing peptide conformations in peptide as- semblies. Such drastic difference in assembling characteristics can be considered as a reflection of asymmetric ad- sorption effect ofpeptides relating to odd-even residue numbers of PolyQ7 and PolyQ8,

关 键 词：PEPTIDE adsorption CONFORMATION odd-even effect scanning tunneling microscopy 

分 类 号：TP311.52[自动化与计算机技术—计算机软件与理论] TN16[自动化与计算机技术—计算机科学与技术]