Folding of peptides

Baum, J., and Brodsky, B. (1999). Folding of peptide models of collagen and misfolding in disease. Curr. Opin. Struct. Biol. 9, 122-128. 

The alternate approach is to make use of the strong metal to ligand bonds to control the folding of peptides and proteins [15 -18,74]. In this way helical pep-... 

From a totally different point of view, Morii and co-workers [70] have studied the utility of synthetic proteins as chiral hosts. They showed that a-helix bundle structures, formed by the folding of peptides such as 75, induced chirality in fluorescent dyes by forming inclusion complexes in the hydrophobic interior of the structures. Again these results can have implications for the development of optical materials and switches. 

The folding of peptide backbones is quite unpredictable. It may assume many forms, such as sinusoidal, saddle, elongated loop, disk, pleated sheet, and helical, e.g., often containing water molecules in interior cavities. The conformation of cyclic peptides can change drastically upon complexation with alkali metal ions. However, there is evidence from crystal structure analyses that conformations of large cyclic peptides are independent of the polarity of solvent, even though the solvent may cocrystallize with the peptide. 

Internal templating refers to the self-selection of library members through intramolecular or intermolecular stabilizing noncovalent interactions. Intramolecular self-templating is observed when the species formed in a DCL are capable of folding upon themselves (Figure 1.2c). The library members that are best able to form favorable noncovalent interactions within themselves will be ampHfied in the library. DCC has therefore been used to study the folding of peptides, nucleotides, and synthetic polymers (Chapter 6). It can be used to direct the reversible... 

The tertiary structure is formed by the folding of peptide chains. Covalent and non-covalent bonds result in the positioning of the secondary structures in relation to each other. Covalent bonds are disulfide bonds between two cysteine units in the protein. Examples of non-covalent bonds are hydrogen bonds, ionic bonds and hydrophobic bmids in the protein. Which type of bond is formed, depends on the length of the peptide chain, pH, electric charge, polarity, and lipophilicity of (secondary) structural elements of the protein. 

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