A thrombus is formed by the aggregation of platelets on the fibrin clot mesh. Because of its ability to induce fibrinolysis, Batroxase reduced the size of an “in vitro” induced thrombus in a 50 μg treatment after 24 hours of incubation, and it completely degraded the thrombus in a 100 μg. With the same amounts, Leucurolysin-a from Bothrops leucurus ( Gremski et al., 2007) was also able

to dissolve a thrombus “in vitro”, with the maximal activity observed for a 100 μg treatment. Batroxase did not affect human platelet aggregation by the agonist ADP. This characteristic capacity has been reported for other PI-class SVMPs, such as Neuwiedase from Bothrops neuwiedi ( Rodrigues et al., 2001) because this class contains only a proteolytic domain. PII class SVMPs possess the proteolytic domain and a disintegrin domain that contains an RGD site that enables Metabolism inhibitor Venetoclax manufacturer interactions with other integrins on platelet surface, thereby preventing platelet aggregation by agonists ( Calvette et al., 1991). In the PIII class SVMPs, such as in Basparin

A from Bothrops asper ( Loría et al., 2003), an additional cysteine-rich domain further facilitates platelet aggregation. Several snake venom metalloproteinases are capable of inducing an incoagulable plasma condition because of their ability to consume plasma coagulation factors (Kamigutti, 2005). Similar to other PI-class SVMPs, Batroxase did not induce plasma coagulation, which facilitates the hemorrhagic process. The primary sequence of Batroxase was determined by N-terminal amino acid sequencing by automatic Edman degradation, and the digested peptides Ergoloid obtained by trypsin proteolysis were sequenced by mass spectrometry. These analyses indicated that

Batroxase is composed of 202 amino acids. Additionally, a primary structure analysis showed that Batroxase lacks N-glycosylation sites (N-X-S/T); its zinc-binding motif (HELGHNLGISH) is fully conserved when compared with that of other SVMPs; and it contains a C164I165 M166 motif associated with a “Met-turn”. PI-class SVMPs may be sub-characterized according to disulfide bridge content (Fox and Serrano, 2005); PIa proteins such as HT-2 from Crotalus ruber ruber, have two disulfide bridges, whereas PIb proteins such as Fibrolase from Agkistrodon contortrix contortrix and Lebetase from Vipera lebetina ( Bello et al., 2006) have three disulfide bridges. Batroxase presented seven cysteine residues that are fully conserved with those in the other metalloproteinases, with matching such as Cys117–Cys197, Cys157–Cys181 and Cys159–Cys164. According to our tertiary structure analyses, Batroxase forms an α-β-α fold that is stabilized by three disulfide bridges (above) similar to those of other class PI SVMPs (Gomis-Rüth et al., 1994, Gong et al., 1998 and Akao et al., 2010) (Fig. 8).