A linear 23-residue peptide reveals a propensity to form an unusual native-like conformation.
A linear 23-residue peptide reveals a propensity to form an unusual native-like conformation.
复制标题
线性 23 个残基肽显示出形成不寻常的类天然构象的倾向。
DOI：
10.1080/07391102.1995.10508853
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发表时间：
1995
影响因子：
4.4
通讯作者：
Ruddon,RW
中科院分区：
文献类型：
--
作者：
Sherman,SA;Gmeiner,WH;Kirnarskiy,L;Perini,F;Ruddon,RW
为了深入了解蛋白质折叠的最早期事件，通过NMR研究了一个23个残基的肽，其序列对应于人绒毛膜促性腺激素β亚基（hCGβ）的38-60片段。在水溶液中，大多数肽残基采用与成熟的、完全折叠的hCGβ中的肽残基相似的延伸的聚脯氨酸II（PII）构象。分离的蛋白质片段即使没有α-螺旋或β-结构也可以获得天然样结构基序的发现，扩展了使用游离肽作为模型系统以更好地理解蛋白质折叠机制的可能性。结果表明，富含PII的结构基序可以有效地确定由NMR光谱。在没有广泛的中程和长程相互作用的情况下，大多数氨基酸残基可能采用PII构象的观察表明，富含PII的结构基序可能在蛋白质折叠的早期事件中发挥重要作用。
To gain insight into the earliest events of protein folding, a 23–residue peptide with a sequence corresponding to the 38–60 fragment of the β-subunit of human chorionic gonadotropin (hCGβ) was studied by NMR. In aqueous solution the majority of the peptide residues adopted an extended polyproline II (PII) conformation similar to those in mature, fully folded hCGβ. The finding that the isolated protein fragment may acquire native-like structural motifs, even without α-helices or β-structures, extends the possibility of using free peptides as model systems to better understand the protein folding mechanisms. It was shown that the PII-rich structural motif can be determined efficiently by NMR spectroscopy. The observation that in the absence of extensive medium- and long-range interactions the majority of amino acid residues may adopt the PIIconformation suggests that the PII-rich structural motifs may play an important role in early events of protein folding.