The versatility of the peptides, in conjunction with their ability to form specific secondary structures, provides a unique platform for the design of nanomaterials with controllable structural features. Oligopeptides fold into secondary structures stabilized by multiple interactions that require the participation of both backbones and side chains. Numerous experimental studies of the conformational characteristics of linear peptides formed by regularly alternating D and L residues have been carried out. These experimental studies have indicated that D,L-alternating peptides are able to assume very specific conformations. Single-stranded beta-helix are symmetrical structures in which the backbone CO and NH groups are oriented quasi-parallel to the helical axis but in alternating opposite directions. They form intrachain hydrogen bonds equivalent in pairs. The side chains are oriented perpendicular to the helical axis on the outside of the helix. These features give rise to compact channel structures with pore size increasing proportionally with the number of residues per turn. Double-stranded beta-helices should be always preferred if the only operative tendency would be that of maximizing the number of H bonds 2. Here we report about the conformational behavior of D,L-alternating peptides containing some glycine residues. Glycine, without sterically restricting side chain allowed motional freedom. Since glycine don't have a chiral C?, can be used to replace both a L- or a D-residue, then we have synthesized some of this peptides (of different length) that, potentially, can assume the same type of conformations of D,L-alternating peptides. This permit us to obtain beta-helical with tunable internal diameter. References: [1] P. De Santis, S. Morosetti, R. Rizzo, Macromolecules, 1974, 7, 52. [2] E. Navarro, E. Fenude, B. Celda, Biopolymers, 2004, 73, 229.
D,L-Alternating Peptides: Utilization of Glycine to Obtain Beta-Helices with Tunable Internal Diameter
E Fenude
2020
Abstract
The versatility of the peptides, in conjunction with their ability to form specific secondary structures, provides a unique platform for the design of nanomaterials with controllable structural features. Oligopeptides fold into secondary structures stabilized by multiple interactions that require the participation of both backbones and side chains. Numerous experimental studies of the conformational characteristics of linear peptides formed by regularly alternating D and L residues have been carried out. These experimental studies have indicated that D,L-alternating peptides are able to assume very specific conformations. Single-stranded beta-helix are symmetrical structures in which the backbone CO and NH groups are oriented quasi-parallel to the helical axis but in alternating opposite directions. They form intrachain hydrogen bonds equivalent in pairs. The side chains are oriented perpendicular to the helical axis on the outside of the helix. These features give rise to compact channel structures with pore size increasing proportionally with the number of residues per turn. Double-stranded beta-helices should be always preferred if the only operative tendency would be that of maximizing the number of H bonds 2. Here we report about the conformational behavior of D,L-alternating peptides containing some glycine residues. Glycine, without sterically restricting side chain allowed motional freedom. Since glycine don't have a chiral C?, can be used to replace both a L- or a D-residue, then we have synthesized some of this peptides (of different length) that, potentially, can assume the same type of conformations of D,L-alternating peptides. This permit us to obtain beta-helical with tunable internal diameter. References: [1] P. De Santis, S. Morosetti, R. Rizzo, Macromolecules, 1974, 7, 52. [2] E. Navarro, E. Fenude, B. Celda, Biopolymers, 2004, 73, 229.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
