title: Structure-activity relationships of sarafotoxins: chemical syntheses of chimera peptides of sarafotoxins S6b and S6c.
abstract: The three chimera peptides of sarafotoxins S6b (SRTb) and S6c (SRTc), [Thr2]SRTb, [Asn4]SRTb and [Glu9]SRTb, were synthesized chemically. From the comparisons of lethality, vasoconstrictor activity and receptor binding activity of SRTb, SRTa [( Asn13]SRTb), SRTc [( Thr2,Asn4,Glu9,Asn13]SRTb), [Thr2]SRTb, [Asn4]SRTb and [Glu9]SRTb, it appears that the Lys9 to Glu9 substitution greatly diminishes these activities while the Lys4 to Asn4 substitution does not affect them, and the Ser2 to Thr2 substitution or the Tyr13 to Asn13 substitution slightly diminishes these activities. These results suggest that the very low activities of SRTc are caused mainly by the Lys9 to Glu9 substitution, but not by the Ser2 to Thr2 substitution, which was suggested to be responsible for the weak bioactivities of SRTd [( Thr2,Ile19]SRTb).
authors.affiliation: Department of Chemistry, Faculty of Science, Tohoku University, Sendai, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Takasaki
authors.forename: S
authors.initials: S
authors.lastname: Aimoto
authors.forename: K
authors.initials: K
authors.lastname: Kitazumi
authors.forename: K
authors.initials: K
authors.lastname: Tasaka
authors.forename: T
authors.initials: T
authors.lastname: Shiba
authors.forename: K
authors.initials: K
authors.lastname: Nishiki
authors.forename: Y
authors.initials: Y
authors.lastname: Furukawa
authors.forename: R
authors.initials: R
authors.lastname: Takayanagi
authors.forename: K
authors.initials: K
authors.lastname: Ohnaka
authors.forename: H
authors.initials: H
authors.lastname: Nawata
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001013:Aorta, Thoracic / Q000378:metabolism; D001665:Binding Sites; D007928:Lethal Dose 50; D008297:Male; D008638:Mesenteric Arteries / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D013329:Structure-Activity Relationship; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000378:metabolism / Q000494:pharmacology*; D014757:Viper Venoms / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D010455:Peptides; D011956:Receptors, Cell Surface; D017466:Receptors, Endothelin; D014662:Vasoconstrictor Agents; D014757:Viper Venoms; C057354:sarafotoxins s6