Glyco‐Scan: Varying Glycosylation in the Sequence of the Peptide Hormone PYY3‐36 and Its Effect on Receptor Selectivity

The increasing prevalence of obesity worldwide calls for safe and highly efficacious satiety drugs. PYY3‐36 has been implicated in food intake regulation, and novel peptide analogues with high Y2 receptor‐subtype selectivity and potency have potential as drugs for the treatment of obesity. It has been hypothesized that PYY3‐36 associates with the plasma membrane prior to receptor activation such that the amphipathic α‐helix of PYY3‐36 possibly guides the C‐terminal pentapeptide into the correct conformation for receptor activation. Ala‐scans are used routinely to study the effect of individual amino acids in a given peptide sequence. Here we report the glyco‐scan of the peptide hormone PYY3‐36, in which hydroxyl side‐chain functionalities were glycosylated; in addition new glycosylation sites were introduced. An array of novel PYY3‐36 analogues with a glycan positioned in the water–membrane interface or in the N terminal were screened for Y‐receptor affinity and selectivity as well as metabolic stability. Interestingly, in contrast to the Y1 and Y4 receptors, the Y2 receptor readily accommodated glycosylations. Especially glycosylations in the α‐helical region of PYY3‐36 were favorable both in terms of Y‐receptor selectivity and endopeptidase resistance. We thus report several PYY3‐36 analogues with enhanced Y‐receptor selectivity. Our results can be used in the design of novel PYY analogues for the treatment of obesity. The glyco‐scan concept, as systematically demonstrated here, has the potential for a wider applicability.