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PubMed · 14505395

Peptide self-replication enhanced by a proline kink.

Xiangqun Li·Jean Chmielewski
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Abstract

The effect of a proline substitution within a self-replicating coiled-coil peptide was investigated. Substitutions at either the d (hydrophobic, XL-1) or e (hydrophilic, XL-2) positions within the coiled-coil led to remarkable self-replication differences. The fragments of XL-1 showed little propensity for ligation even in the presence of template, whereas XL-2 demonstrated a high catalytic efficiency for self-replication. These results may be due to intrinsic differences in the bend of the helical axis within the two peptides away from the side with the proline residue, resulting in the loss of the continuous hydrophobic interface within XL-1.

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Circular DichroismPeptidesProlineProtein FoldingProtein Structure, SecondaryJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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Xiangqun Li, Jean Chmielewski. 2003-10-01. Peptide self-replication enhanced by a proline kink.. https://doi.org/10.1021/ja036569s

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