title: Biochemical and functional properties of a thrombin-like enzyme isolated from Bothrops pauloensis snake venom.
abstract: In the present study, a thrombin-like enzyme named BpSP-I was isolated from Bothrops pauloensis snake venom and its biochemical, enzymatic and pharmacological characteristics were determined. BpSP-I is a glycoprotein that contains both N-linked carbohydrates and sialic acid in its structure, with M(r)=34,000 under reducing conditions and pI approximately 6.4. The N-terminal sequence of the enzyme (VIGGDECDINEHPFL) showed high similarity with other thrombin-like enzymes from snake venoms. BpSP-I showed high clotting activity upon bovine and human plasma and was inhibited by PMSF, benzamidine and leupeptin. Moreover, this enzyme showed stability when examined at different temperatures (-70 to 37 degrees C), pH values (3-9) or in the presence of divalent metal ions (Ca(2+), Mg(2+), Zn(2+) and Mn(2+)). BpSP-I showed high catalytic activity upon substrates, such as fibrinogen, TAME, S-2238 and S-2288. It also showed kallikrein-like activity, but was unable to act upon factor Xa and plasmin substrates. Indeed, the enzyme did not induce hemorrhage, myotoxicity or edema. Taken together, our data showed that BpSP-I is in fact a thrombin-like enzyme isoform isolated from Bothrops pauloensis snake venom.
authors.affiliation: Instituto de Genética e Bioquímica, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
authors.forename: Fábio L S
authors.initials: FL
authors.lastname: Costa
authors.forename: Renata S
authors.initials: RS
authors.lastname: Rodrigues
authors.forename: Luiz F M
authors.initials: LF
authors.lastname: Izidoro
authors.forename: Danilo L
authors.initials: DL
authors.lastname: Menaldo
authors.forename: Amélia
authors.initials: A
authors.lastname: Hamaguchi
authors.forename: Maria I
authors.initials: MI
authors.lastname: Homsi-Brandeburgo
authors.forename: André L
authors.initials: AL
authors.lastname: Fuly
authors.forename: Sandro G
authors.initials: SG
authors.lastname: Soares
authors.forename: Heloisa S
authors.initials: HS
authors.lastname: Selistre-de-Araújo
authors.forename: Benedito
authors.initials: B
authors.lastname: Barraviera
authors.forename: Andreimar M
authors.initials: AM
authors.lastname: Soares
authors.forename: Veridiana M
authors.initials: VM
authors.lastname: Rodrigues
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017837:Bothrops; D003435:Crotalid Venoms / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D013917:Thrombin / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D003435:Crotalid Venoms; D013917:Thrombin