Thrombin-like enzyme from Lachesis muta muta venom: Isolation and topographical analysis of its active site structure by means of the binding of amidines and guanidines as competitive inhibitors

Affinity purification of serine proteinase from Deinagkistrodon acutus venom

“…7.5 mg of active protein was obtained with a total yield of 3.6% from crude venom protein (Table 1), it is the main serine proteinase in D. acutus venom. The whole process of affinity chromatography and ion-exchange chromatography only takes less than 4 h. The serine proteinase protein yield of this affinity protocol 3.6%, compared with serine proteinase protein yield of traditional methods, as 1.6% of Wang et al [9], 0.8% of Oyama and Takahashi [14], 2.1% of Magalhaes et al [13], 3.4% of Magalhaes et al [11], is higher.…”

“…Purification protocols of serine proteinases from snake venoms usually consist of three or more steps of gel-filtration and ion-exchange chromatography [7,9,13,15], and agmatine affinity chromatography was incorporated along with gel-filtration chromatography [14,16,21]. However, the protein yield and activity recoveries were low.…”

“…one approach with two ion-exchange chromatographies on DEAE-Sepharose, one on MonoQ, and one gel-filtration on Superose 12 [7], the other approach with one ion-exchange chromatography on DEAE-Trisacryl, one gel-filtration on TSK G2000SW, and one reverse-phase chromatography on Vydac RP-C 4 [9] or other combination of gel-filtration chromatographies and ion-exchange chromatography [12,14]. Improvement has been made with agmatine and benzamidine affinity chromatography incorporated along with gel-filtration chromatography [11,13]. However, the sample capacity and inefficiency of gel-filtration chromatography step made the protocol time consuming and productivity low in production scale [7,9,12,14].…”

Proteolytic truncation of human transthyretin linked to amyloidosis is mediated by a trypsin like enzyme: In vitro demonstration using model peptides

“…This is described as a moderate inhibitor with measured K i ~126 μM (Figure 4). Although our finding of DMF as an inhibitor of trypsin is quite unexpected and accidental but it is not completely unrealistic since compounds containing similar functional moiety such as benzamidines, guanidines and even amides have been reported to inhibit in vitro protease activity of serine proteases like thrombin, trypsin etc [54,55].…”

“…All synthetic hTTR [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60] peptides namely the wild type P1, along with the mutant peptides S 52 /P (P2), K 48 /A (P3) and T 49 /A(P4) ( Table 1) were analysed based on their 3-D in vacuo generated energy minimised model structures. These structures were obtained by Hyperchem software professional program (v 11.0.…”