Selective binding of two-armed diketopiperazine receptors to side-chain-protected peptides

The binding properties of two-armed receptors based on a diketopiperazine template toward side-chain-protected peptides have been elucidated. Selective binding of these diketopiperazine receptors is not limited to side-chain-free peptides, but combinatorial on-bead assays show that also side-chain-protected peptides are recognized with high specificity. Furthermore, the screening of several dye-marked diketopiperazine receptors against an encoded side-chain-protected tripeptide library demonstrated not only their high binding specificities but also revealed that small structural changes suffice to alter the binding preferences significantly.     

Peptide damage under Fenton conditions is sequence-dependent

Peptides with two or more acidic amino acids are damaged to a greater extent than other peptides under Fenton conditions as revealed by treating a 29791 membered one-bead-one-compound peptide library with FeCl(3), sodium ascorbate and hydrogen peroxide.     

Determination of binding affinities on solid supports: influence of the loading and the nature of the solid support

The scope of a solid phase binding assay for the determination of binding affinities between a solid supported substrate and a coloured host has been studied by investigating the influence of the nature and the loading of the solid support.     

Macrocyclic diketopiperazine receptors: effect of macrocyclization on the binding properties of two-armed receptors

The synthesis of macrocyclic two-armed diketopiperazine receptors and their binding properties toward peptides is described. Macrocyclization with short linkers led to receptors with significantly modified binding properties compared to their flexible open chain parent receptors, whereas with long linkers the original binding selectivities were largely retained.