Cyclodextrin-peptide hybrid as a hydrolytic catalyst having multiple functional groups

Synthesis of a chitosan-based functional biopolymer with both catalytic and binding groups for protein and DNA hydrolysis

Protein and DNA hydrolysis by chitosan-based biopolymer with catalytic and binding groups.

Carbohydrates in peptide and protein design

Monosaccharides and amino acids are fundamental building blocks in the assembly of nature's polymers. They have different structural aspects and, to a significant extent, different functional groups. Oligomerization gives rise to oligosaccharides and peptides, respectively. While carbohydrates and peptides can be found conjoined in nature, e.g., in glycopeptides, the aim of this review is the radical redesign of peptide structures using carbohydrates, particularly monosaccharides and cyclic oligosaccharides, to produce novel peptides, peptidomimetics, and abiotic proteins. These hybrid molecules, chimeras, have properties arising largely from the combination of structural characteristics of carbohydrates with the functional group diversity of peptides. This field includes de novo designed synthetic glycopeptides, sugar (carbohydrate) amino acids, carbohydrate scaffolds for nonpeptidal peptidomimetics of cyclic peptides, cyclodextrin functionalized peptides, and carboproteins, i.e., carbohydrate-based proteinmimetics. These successful applications demonstrate the general utility of carbohydrates in peptide and protein architecture.

Enantioselective ester hydrolysis catalyzed by β-cyclodextrin conjugated with β-hairpin peptides

Designed cyclodextrin-peptide conjugates, which have one or two beta-hairpin peptides, have been synthesized as catalysts for ester hydrolysis. One or two beta-hairpin peptides were located at the primary hydroxyl group side of beta-cyclodextrin so as to arrange two histidine residues that act as a general acid and a general base catalysts and provide the substrate recognition subsite. Kinetic studies revealed that the two-beta-hairpin peptide was more effective than that of the one-beta-hairpin peptide for substrate recognition.

Emerging principles of de novo catalyst design

Considerable progress has been made in the understanding of how to exploit hydrophobic and charge-charge interactions in forming binding sites for peptides and small molecules in folded polypeptide catalysts. This knowledge has enabled the introduction of feedback and control functions into catalytic cycles and the construction of folded polypeptide catalysts that follow saturation kinetics. Major advances have also been made in the design of metalloproteins and metallopeptides, especially with regards to understanding redox potential control.