title: A high affinity, mu-opioid receptor-selective enkephalin analogue lacking an N-terminal tyrosine.
abstract: We report a high affinity, mu opioid receptor selective enkephalin analogue in which the N-terminal tyrosine residue thought to be required for such high affinity is replaced by phenylalanine. The high affinity can be traced to a shift of the ligand's N-terminal residue within the mu receptor binding pocket, which diminishes the importance of the usual hydrogen bond between the tyrosine phenolic moiety and the receptor.
authors.affiliation: College of Pharmacy, University of Michigan, Ann Arbor 48109, USA.
authors.forename: H I
authors.initials: HI
authors.lastname: Mosberg
authors.forename: J C
authors.initials: JC
authors.lastname: Ho
authors.forename: K
authors.initials: K
authors.lastname: Sobczyk-Kojiro
mesh_terms: D004745:Enkephalins / Q000138:chemical synthesis / Q000378:metabolism* / Q000494:pharmacology*; D007700:Kinetics; D010456:Peptides, Cyclic / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D017450:Receptors, Opioid, mu / Q000187:drug effects* / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014443:Tyrosine / Q000737:chemistry*
chemical_list: D004745:Enkephalins; D010456:Peptides, Cyclic; D017450:Receptors, Opioid, mu; D014443:Tyrosine