Peptides artificial

Matsumura S, Ajima K, Yudasaka M, Iijima S, Shiba K (2007) Dispersion of cisplatin-loaded carbon nanohoms with a conjugate comprised of an artificial peptide aptamer and polyethylene glycol. Molecular Pharmacology. 4 723-729. 

This concept of reversible chemical crosslinking of the chains to drastically decrease the enthalpic penalty of the folding process and to exploit the highly favored disulfide loop formation in the A-chain with m = 4, has been further developed into artificial peptide linker chains that can be excised selectively by enzymatic processing, to allow for bioexpression of the artificial proinsulins on an industrial scale. 95,96 However, to apply this approach rationally to other double-stranded cystine peptides, knowledge about their three-dimensional structure is essential. 

Fig. 28. Schematic illustration of an artificial peptidic electron-transfer system designed to operate in a bilayer membrane. (Reproduced with the permission of Ref. 69)...

Artificial peptides, such as GALA and JTS-1, and the sequence of the /V-terminal segment of VP1 of HRV2 rhinovirus, have also been found to enhance the transfection efficiency of polylysine conjugates/ DNA complexes (Table 16.1). These peptides, which contain acid residues (mainly glutamate) were shown to induce membrane fusion and permeabilization at pH lower than 6. Permeabilization and fusion activities... 

Schmuck, C., How to improve guanidinium cations for oxoanion binding in aqueous solution The design of artificial peptide receptors , Coord. Chem. Rev. 2006, 250, 3053-3067. 

In medicinal chemistry we can use isolated, well-defined artificial peptides made from a few amino acid residues only, and which have a specific microstructure, to investigate the biological function of a selected peptide segment of a large protein (see also Chapter 1.2). It is, therefore, an important challenge in bioorganic chemistry to stabilize specific conformations of amino acids and small peptides to fix defined three-dimensional structures [2, 3]. 

Some natural ion channels are believed to form amphiphilic a-helix bundles in hydrophobic lipid membranes, where the a-helices assemble with their hydrophilic parts facing each other, resulting in a hydrophilic channel. If artificial peptides that had appropriate combinations of both hydrophobic amino acid residues and hydrophobic amino acid sequences were used, the peptides would self-assemble to form a hydrophilic pathway in the lipid membrane. 

Focusing on the proteasome, a general decline of the proteasomal system was found in aged tissue cultures. This includes the decreased activity of the proteasome towards artificial peptide substrates as well as the ability to degrade oxidized model proteins [59-61]. 

Quite recently we synthesized truly biomimetic receptors which contain, as spacers between crown ether and ammonium units, peptides instead of unnatural spacers as in 14 and IS. Host compounds such as 21 not only discriminate natural peptides by length and sequence, but are capable, in principle, of chiral recognition. They allow one to study in various media the energetics of side-chain interactions in P-sheet-like structures in a systematic way, exemplifying both the practical and the theoretically interesting aspects in the development of artificial peptide receptors. 

By using KLKL5KLK and its derivatives, it was shown for the first time that an artificial peptide could prevent infections with S. aureus in mice [30]. In addition to their direct antibacterial effects, it is thought that the chemotherapeutical activity of KLKL5KLK and its derivatives is due to the activation of neutrophils. Experiments... 

The surface plasmon resonance experiments with artificial peptides demonstrated that a peptide with the sequence... 

The design of artificial peptide sequences for the preparation of responsive surfaces takes advantage of the wealth of literature and information available on how the sequence of amino acids in a peptide chain affect the overall properties of the peptide (Boyle Woolfson, 2011 Bromley et al., 2008). The two general strategies employed so far are the exploitation of charge effects on the secondary conformation of the peptide and the ability of dipole moments of helical peptides to direct an electric current (Figure 3.5). 

Site-directed immobilization is the connection of ligand at a defined point to orientate the ligand optimally for specific interaction. This is shown schematically in Fig. 11 for an artificial peptide. 

Nanofiber Formation from Artificial Peptides and Peptidomimetics... 

Abstract Molecular self-assembly is a powerful approach being explored for novel supra-molecular nanostructures and bio-inspired nanomaterials. In this article, we focus on recent research concerning the self-assembly of de novo designed artificial peptides and peptidomimetics into nanofiber structures, specifically towards developing a new class of soft-materials. These nanofiber architectures have potential use not only in biomedical applications, such as 3D-matrix scaffolds for tissue engineering and biomineralization, but also in nanotechnology such as nano-templates and dimension-regulated functional nano-objects. 

Keywords Artificial peptides Coiled-coil structure Helix structure ... 

In this section, we focus on the research of S-sheet-based self-assembled nanofibers from de novo designed artificial peptides and peptidomimetics aimed for applying in materials science. 

Three main types of artificial peptide motifs have been developed to construct 6-sheet-based nanofibers through self-assembly, as shown in Fig. 1. These peptides and peptidomimetics have hydrophobic and hydrophilic segments as a common feature. The hydrophobic segment seems to provide an important driving force for self-assembly, as well as hydrogen bonding and electrostatic interactions, especially in aqueous media. 

Fig.1 Chemical structures of various types of artificial peptides and peptidomimetics (type I-III) that self-assemble into )0-sheet-based nanofibers...

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