Site-specific modification of de novo designed coiled-coil polypeptides with inorganic redox complexes.
Site-specific modification of de novo designed coiled-coil polypeptides with inorganic redox complexes.
复制标题
用无机氧化还原复合物对从头设计的卷曲螺旋多肽进行位点特异性修饰。
DOI：
10.1021/bc015544k
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发表时间：
2002
影响因子：
4.7
通讯作者：
Ogawa,MichaelY
中科院分区：
文献类型：
--
作者：
Fedorova,Anna;Ogawa,MichaelY
描述了一种制备位点特异性双核金属肽的分步方法。修饰过程包括通过与[Ru（bpy）2（phen-ClA）]2+反应使半胱氨酸侧链烷基化，其中bpy = 2，2 ′-联吡啶，phen-ClA = 5-氯乙酰氨基-1，10-菲咯啉，然后将钌五氨络合物配位到位于序列沿着其它位置的组氨酸残基上。脱辅基肽和金属化肽C10 H21（30-mer）和H10 C21（30-mer）的圆二色性光谱在208和222 nm处具有最小值，θ222/θ208= 1.04，表明这些肽在水溶液中以α-螺旋卷曲螺旋存在。当钌多吡啶络合物连接到C10 H21（30-mer）时，所得金属肽的Δ-和Δ-I非对映体可以容易地通过反相HPLC彼此分离。然而，在相关的H10 C21（30聚体）金属肽的情况下，这两个非对映异构体不能通过色谱分离。这些结果表明肽构象/序列和金属络合物几何形状之间的微妙相互作用可能会改变金属肽的一些物理特性。
A stepwise procedure for preparing of site-specific binuclear metallopeptides is described. The modification procedure involves the alkylation of a cysteine side chain by reaction with [Ru(bpy)2(phen-ClA)]2+, where bpy = 2,2‘-bipyridine and phen-ClA = 5-chloroacetamido-1,10-phenanthroline, followed by the coordination of a ruthenium pentammine complex to a histidine residue located elsewhere along the sequence. The apo and metalated versions of the peptides C10H21(30-mer) and H10C21(30-mer) display circular dichroism spectra having minima at 208 and 222 nm, with θ222/θ208= 1.04 to indicate that these peptides exist as α-helical coiled-coils in aqueous solution. When the ruthenium polypyridyl complex is attached to C10H21(30-mer), the Δ-land Λ-ldiastereomers of the resulting metallopeptide can be readily separated from each other by reversed-phase HPLC. However, in the case of the related H10C21(30-mer) metallopeptide, the two diastereomers cannot be chromatographically resolved. These results indicate how the subtle interplay between peptide conformation/sequence and metal complex geometry may alter some of the physical characteristics of metallopeptides.