Peptide secondary structure

The effect of C ,C -disubstituted amino acids (aaAAs) on peptide secondary structure has been studied in recent years.2a d While longer side-chain C ,C -di-n-alkyl amino acids promote extended peptide conformation,23 alicyclic aaAAs, in which the Ca carbon forms a cyclic bridge with itself, such a 1-aminocyclopentane-l-carboxylic acid (Ac5c) and 1-aminocyclohexane-l-carboxylic acid (Ac6c), have helix-forming characteristics similar to those of 1 -aminoisobutyric acid (Aib).2ax... 

Lelais G, Seebach D, Jaun B, Mathad RI, Flogel O, Rossi F, Campo M, Wort-mann A (2006) Beta-Peptidic Secondary Structures fortified and enforced by Zn2+ Complexation - On the Way to Beta-Peptidic Zinc Fingers Helv Chim Acta 89 361 103... 

Eguchi M, McMillan M, Nguyen C, et al. (2003) Chemogenomics with peptide secondary structure mimetics. Comb. Chem. High Throughput Screen. 6 611-621. 

As part of their exploration of peptide secondary structure, Hermkens et al. (154) reported an innovative use of the nitrone dipolar cycloaddition... 

Possible ackbtine/Side-Chain Ca-Cfi Spatiui Projections oj he Intramolecular Bonding in Peptide Secondary Structure... 

During the preparation of this chapter, a review on the use of templates to induce peptide secondary structures appeared Scheiner JP, Kelly JW (1995) Chem Rev 95 2169... 

The dependence of the principal components of the nuclear magnetic resonance (NMR) chemical shift tensor of non-hydrogen nuclei in model dipeptides is investigated. It is observed that the principal axis system of the chemical shift tensors of the carbonyl carbon and the amide nitrogen are intimately linked to the amide plane. On the other hand, there is no clear relationship between the alpha carbon chemical shift tensor and the molecular framework. However, the projection of this tensor on the C-H vector reveals interesting trends that one may use in peptide secondary structure determination. Effects of hydrogen bonding on the chemical shift tensor will also be discussed. The dependence of the chemical shift on ionic distance has also been studied in Rb halides and mixed halides. Lastly, the presence of motion can have dramatic effects on the observed NMR chemical shift tensor as illustrated by a nitrosyl meso-tetraphenyl porphinato cobalt (III) complex. 

Synthesis and Application of Proline and Pipecolic Acid Derivatives Tools for Stabilization of Peptide Secondary Structures... 

Modified 7- and 10-membered cyclic peptides as mimetics of peptide secondary structure 93SL821. 

Vener MV, Egorova AN, Fomin DP, Tsirelson VG (2007) QTAIM study of the closed-shell interactions in peptide secondary structures A cluster treatment of oligo- and poly alanines. Chem Phys Lett... 

Keiderling TA, Kubelka J, Hilario J (2006) Contribution of transition dipole coupling to amide coupling in IR spectra of peptide secondary structures. Vibrational Spectroscopy of Biological and Polymer Materials 253-324... 

Figure 4a. Stereo figure of the peptide secondary structure of the right-handed ct-helix (aR). This and Figures 4b, 4c, and 4d are the final structures that result from the minimization of the energy as described (dE/dx = 0). The first three N-H bonds do not form hydrogen bonds. The last hydrogen bond is slightly...

Figure 4b. Stereo figure of the peptide secondary structure of the left-handed arhelix (aL). Minimization results in distortion at the ends. At the C-terminal end a ten-membered hydrogen bonded ring has been formed, and at the N-terminal end the peptide group has twisted out of the plane. (Compare with the structure of the...

Figure 4c. Stereo figure of the peptide secondary structure of the extended C-7 equatorial helix (C7eq)- This structure is formed by repeating seven-membered rings.

M. Kahn, Peptide secondary structure mimetics applications to vaccines and pharmaceuticals. Farmaco 1996, 51, 87-96. 

Martinek TA, Fiilop F. Side-chain control of P-peptide secondary structures. Design principles. Fur. J. Biochem. 2003 270 3657-3666. 

Peptide 1 and glycopeptides 2-6 synthesized in order to probe the infiuence of asparagine-linked glycosylaUon on peptide secondary structure [67,68,69]... 

For /1-peptide secondary structures, cooperative formation has been investigated in various ways. One test of cooperativity involves examining the onset of conformational order as a function of chain length. The earliest study of this sort for discrete /1-peptide oligomer appears to date back to 1979 on poly(S-/lAspOiBu).198 However, at that time the structure of the ordered conformation was not understood. Clues about cooperativity in forming the 14-helix with /1-peptides can be found from CD studies. Figure 37 shows a plot of CD intensity (normalized per... 

Continued investigation of novel scaffolds that can mimic peptide secondary structures (4> and if/ space), such as a-helices, j3-tums, -sheets peptide topographical structures (chi space) and, most challenging, that can mimic protein conformational changes such as a-helix to /3-sheet transitions. 

Fig. 9. Dependence of the C chemical shift tensor in glycine on different types of peptide secondary structure motifs, from an experimental investigation of tripeptides.

Keywords Block copolymer Peptide Secondary structure Self-assembly Vesicle Hierarchical structure... 

Halab, L., Gosselin, R, and Lubell, W. D. (2000) Design, synthesis, and conformational analysis of azacycloalkane amino acids as conformationally constrained probes for mimicry of peptide secondary structures. Biopolymers 55, 101-122. 

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