Designed Peptides with Homochiral and Heterochiral Diproline Templates as Conformational Constraints
作者:Bhaswati Chatterjee、Indranil Saha、Srinivasarao Raghothama、Subrayashastry Aravinda、Rajkishor Rai、Narayanaswamy Shamala、Padmanabhan Balaram
DOI:10.1002/chem.200702029
日期:2008.7.7
of Piv-D-Pro-L-Pro-D-Ala-NHMe (11). An analysis of pyrrolidine conformations suggests a preferred proline puckering geometry is favored only in the case of heterochiral diproline segments. Solution NMR studies, reveal a strong conformational influence of the C-terminal Xxx residues on the structures of diproline segments. In L-Pro-L-Pro-L-Xxx sequences, the Xxx residues strongly determine the population
已经将双脯氨酸片段作为用于设计的肽中的折叠结构成核的模板。通过对包含L-Pro-L-Pro和D-Pro-L-Pro单元的模型肽进行晶体学和NMR研究,已经探究了可用于同手性和异手性双脯氨酸片段的构象空间。已经研究了四种不同类别的模型肽:a)分离的D-Pro-L-Pro片段,形成II'型β-转角;b)D-Pro-L-Pro-L-Xxx序列,形成II'-I型(betaII'-I,连续的beta圈)圈;c)D-Pro-L-Pro-D-Xxx序列;d)L-Pro-L-Pro-L-Xxx序列。报道了总共17个含有双脯氨酸片段的肽晶体结构。Piv-D-Pro-L-Pro-L-Xxx-NHMe类型的肽构象均一,采用连续的β-转角构象。Piv-D-Pro-L-Pro-D-Xxx-NHMe系列和Piv-L-Pro-L-Pro-L-Xxx-NHMe系列中的肽在晶体中显示结构异质性。在Piv-L-Pro-L-P