Use of Constrained Synthetic Amino Acids in -Helix Proteins for Conformational Control
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- 作者：David Zanuy ; Ana I. Jimé ; nez ; Carlos Cativiela ; Ruth Nussinov ; Carlos Alemá ; n
- 刊名：Journal of Physical Chemistry B
- 出版年：2007
- 出版时间：March 29, 2007
- 年：2007
- 卷：111
- 期：12
- 页码：3236 - 3242
- 全文大小：332K
- 年卷期：v.111,no.12(March 29, 2007)
- ISSN：1520-5207
文摘
A highly constrained amino acid has been introduced in the turn region of a 
-helix to increase theconformational stability of the native fold for nanotechnological purposes. The influence of this specificamino acid replacement in the final organization of -helix motifs has been evaluated by combining ab initiofirst-principles calculations on model systems and molecular dynamics simulations of entire peptide segments.The former methodology, which has been applied to a sequence containing three amino acids, has been usedto develop adjusted templates. Calculations indicated that 1-amino-2,2-diphenylcyclopropanecarboxylic acid,a constrained cyclopropane analogue of phenylalanine, exhibits a strong tendency to form and promote foldedconformations. On the other hand, molecular dynamics simulations are employed to probe the ability of sucha synthetic amino acid to enhance the conformational stability of the -helix motif, which is the first requirementfor further protein nanoengineering. A highly regular segment from a naturally occurring -helix protein wasselected as a potential nanoconstruct module. Simulations of wild type and mutated segments revealed thatthe ability of the phenylalanine analogue to nucleate turn conformations enhances the conformational stabilityof the -helix motif in isolated peptide segments.
-helix to increase theconformational stability of the native fold for nanotechnological purposes. The influence of this specificamino acid replacement in the final organization of -helix motifs has been evaluated by combining ab initiofirst-principles calculations on model systems and molecular dynamics simulations of entire peptide segments.The former methodology, which has been applied to a sequence containing three amino acids, has been usedto develop adjusted templates. Calculations indicated that 1-amino-2,2-diphenylcyclopropanecarboxylic acid,a constrained cyclopropane analogue of phenylalanine, exhibits a strong tendency to form and promote foldedconformations. On the other hand, molecular dynamics simulations are employed to probe the ability of sucha synthetic amino acid to enhance the conformational stability of the -helix motif, which is the first requirementfor further protein nanoengineering. A highly regular segment from a naturally occurring -helix protein wasselected as a potential nanoconstruct module. Simulations of wild type and mutated segments revealed thatthe ability of the phenylalanine analogue to nucleate turn conformations enhances the conformational stabilityof the -helix motif in isolated peptide segments.