title: Biological and biochemical characterization of venom from the broad-banded copperhead (Agkistrodon contortrix laticinctus): isolation of two new dimeric disintegrins.
abstract: Disintegrins represent a family of effective cell-cell and cell-matrix inhibitors by binding to integrin receptors. Integrins are heterodimeric, transmembrane receptors that are the bridges for these cell interactions. Disintegrins have been shown to have many therapeutic implications for the treatment of strokes, heart attacks, and cancer. Two novel heterodimeric disintegrins were isolated from the venom of the broad-banded copperhead (Agkistrodon contortrix laticinctus). Crude venom separated by cation-exchange chromatography resulted in several fractions possessing hemorrhagic, fibrinolytic, gelatinase, and platelet activities. Venom fractions 2-3 and 17-19 showed fibrinolytic activity. Fractions 2-6, 8-11, and 16-21 had hemorrhagic activity. Gelatinase activity was found in fractions 3, 11, and 19. The isolation of laticinstatins 1 and 2 was accomplished by fractionating crude venom using reverse phase chromatography. Data from both SDS-PAGE and N-terminal sequencing determined that laticinstatins 1 and 2 were heterodimeric disintegrins, and both were assayed for their ability to inhibit platelet aggregation in human whole blood. Future functional evaluation of snake venom disintegrins shows considerable promise for elucidating the biochemical mechanisms of integrin-ligand interactions that will allow the development of adequate medications for hemostatic pathologies such as thrombosis, stroke, and cerebral and cardiac accidents. In this study, we are presenting the first report of the purification, and partial characterization of two new dimeric disintegrins isolated from the venom of broad-banded copperhead snakes.
authors.affiliation: Laboratorio de Inmunoquímica y Ultraestructura, Instituto Anatómico de la Universidad Central de Venezuela, Ciudad Universitaria, Caracas 1041, Venezuela.
authors.forename: Alexis
authors.initials: A
authors.lastname: Rodríguez-Acosta
authors.affiliation: National Natural Toxins Research Center (NNTRC), Texas A&M University-Kingsville, MSC 158, 975 West Avenue B, Kingsville, TX 78363, USA.
authors.forename: Sara
authors.initials: S
authors.lastname: Lucena
authors.affiliation: Biology Department, Del Mar College, 101 Baldwin Blvd., Corpus Christi, TX 78404, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Alfonso
authors.affiliation: Biology Department, Del Mar College, 101 Baldwin Blvd., Corpus Christi, TX 78404, USA.
authors.forename: Amber
authors.initials: A
authors.lastname: Goins
authors.affiliation: National Natural Toxins Research Center (NNTRC), Texas A&M University-Kingsville, MSC 158, 975 West Avenue B, Kingsville, TX 78363, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Walls
authors.affiliation: Laboratorio de Fisiopatología, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, Caracas 1020A, Venezuela.
authors.forename: Belsy
authors.initials: B
authors.lastname: Guerrero
authors.affiliation: National Natural Toxins Research Center (NNTRC), Texas A&M University-Kingsville, MSC 158, 975 West Avenue B, Kingsville, TX 78363, USA.
authors.forename: Montamas
authors.initials: M
authors.lastname: Suntravat
authors.affiliation: National Natural Toxins Research Center (NNTRC), Texas A&M University-Kingsville, MSC 158, 975 West Avenue B, Kingsville, TX 78363, USA.
authors.forename: Elda E
authors.initials: EE
authors.lastname: Sánchez
keywords: Agkistrodon contortrix laticinctus; broad-banded copperhead; disintegrins; platelet aggregation; venom