Semisynthesis of a glycosylated lm7 analogue for protein folding studies
Semisynthesis of a glycosylated lm7 analogue for protein folding studies
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DOI：
10.1021/ja051855k
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发表时间：
2005-09-21
影响因子：
15
通讯作者：
Imperiali, B
中科院分区：
文献类型：
--
作者：
Hackenberger, CPR;Friel, CT;Imperiali, B
为了建立一个系统来解决糖基化对蛋白质折叠途径的影响问题，我们开发了免疫蛋白lm7的半合成途径。这种四螺旋蛋白已被广泛用作折叠研究的模型蛋白。天然化学连接（NCL）提供了一种具有Ala29Cys突变的lm7的n -连接壳聚糖糖蛋白类似物。半合成方法依赖于糖基化或非糖基化形式的n端硫酯（包括螺旋I）的固相肽合成（SPPS），结合lm7的c端片段（包含螺旋II-IV）的表达。蛋白质折叠行为的详细动力学和热力学分析表明，半合成的lm7类似物非常适合蛋白质折叠研究，并且该lm7变体的糖蛋白的折叠机制与未糖基化的类似物相比没有显着改变。
To establish a system to address questions concerning the influence of glycosylation on protein folding pathways, we have developed a semisynthetic route toward the immunity protein lm7. This four-helix protein has been used extensively as model protein for folding studies. Native chemical ligation (NCL) affords an N-linked chitobiose glycoprotein analogue of lm7 with an Ala29Cys mutation. The semisynthetic approach relies on the solid-phase peptide synthesis (SPPS) of N-terminal thioesters (including helix I), in glycosylated or unglycosylated form, in combination with the expression of the C-terminal fragment of lm7 (containing helices II-IV). Detailed kinetic and thermodynamic analysis of the protein folding behavior reveals that semisynthetic lm7 analogues are well suited for protein folding studies and that the folding mechanism of the glycoprotein of this lm7 variant is not significantly altered over the unglycosylated analogue.