title: [Site-directed mutagenesis of the gene of Echistatin Leu14-Lys15-Glu16].
abstract: In order to probe relationship of inhibition activity of platelet aggregation and RGD conformation beneficial to binding in Echistatin, we used the site-directed mutation technique to install another RGD sequence into one of irregular loops retaining a degree of conformational flexibility and substituting Leu-14, Lys-15, Glu-16 of (Leu-28) Echistatin. The mutant (Arg-14, Gly-15, Asp-16, Leu-28) Echistatin did not lose its inhibition activity of platelet aggregation; however, it showed at least as high activity as (Leu-28) Echistatin, or even a little higher than (Leu-28) Echistatin. This suggested that both RGD sequences inserted in one loop with a degree of conformational flexibility. The original RGD (Arg-24, Gly-25, Asp-26) motif projecting significantly from the surface of the scaffold or core might contribute synergistically to the function of inhibiting platelet aggregation induced by 10 mumol/ L ADP (final concentration). These results are useful in the elucidation of the relationship of structure and function of Echistatin-like disintegrins and GPIIb/IIIa-like integrins.
authors.affiliation: College of Life Sciences, Peking University, Beijing.
authors.forename: H
authors.initials: H
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: M
authors.initials: M
authors.lastname: Hu
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009842:Oligopeptides / Q000737:chemistry; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D013329:Structure-Activity Relationship; D014757:Viper Venoms / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D009842:Oligopeptides; D010455:Peptides; D010975:Platelet Aggregation Inhibitors; D014757:Viper Venoms; C057986:echistatin; C047981:arginyl-glycyl-aspartic acid