Biochemical Characterization and Pharmacological Properties of New Basic PLA₂BrTX-I Isolated fromBothrops roedingeri(Roedinger's Lancehead) Mertens, 1942, Snake Venom

Abstract

BrTX-I, a PLA2, was purified from Bothrops roedingeri venom after only one chromatographic step using reverse-phase HPLC on μ-Bondapak C-18 column. A molecular mass of 14358.69 Da was determined by MALDI-TOF mass spectrometry. Amino acid analysis showed a high content of hydrophobic and basic amino acids as well as 14 half-cysteine residues. The total amino acid sequence was obtained using SwissProt database and showed high amino acid sequence identity with other PLA2 from snake venom. The amino acid composition showed that BrTX-I has a high content of Lys, Tyr, Gly, Pro, and 14 half-Cys residues, typical of a basic PLA2. BrTX-I presented PLA2 activity and showed a minimum sigmoidal behavior, reaching its maximal activity at pH 8.0, 35–45°C, and required Ca2+. In vitro, the whole venom and BrTX-I caused a neuromuscular blockade in biventer cervicis preparations in a similar way to other Bothrops species. BrTX-I induced myonecrosis and oedema-forming activity analyzed through injection of the purified BrTX-I in mice. Since BrTX-I exerts a strong proinflammatory effect, the enzymatic phospholipid hydrolysis might be relevant for these phenomena; incrementing levels of IL-1, IL-6, and TNFα were observed at 15 min, 30 min, one, two, and six hours postinjection, respectively.

PhTX-II a Basic Myotoxic Phospholipase A2 from Porthidium hyoprora Snake Venom, Pharmacological Characterization and Amino Acid Sequence by Mass Spectrometry

“…The PhTX-II PLA 2 is an enzyme composed of a unique polypeptidic chain revealed by Tricine SDS-PAGE with molecular mass of 14,149.08 Da confirmed by mass spectrometry ( Figure 2 ). This value is similar to other isolated myotoxic PLA 2 from snake venom [ 20 , 21 , 22 ].…”

Novel acidic phospholipase A2 from Porthidium hyoprora causes inflammation with mast cell rich infiltrate

“…Research using a PLA 2 isolated from Bothrops roedingeri revealed high inflammatory capabilities, with a similar behavior [12] . As stated by the researcher, TNF-α, is likely to be induced by PLA 2 action, which would induce the expression of selectins resulting in release of other interleukins, such as IL-1 and IL-6.…”

“…Dominici staining made possible the identification of these as mast cells, as suspected by previous observations in sections stained with HE. Since there was no tissue damage or hemorrhage caused by PhTX-III, the source of cytokines can be explained by mast cell degranulation [12] , [34] .…”

Biological characterization of the Amazon coral Micrurus spixii snake venom: Isolation of a new neurotoxic phospholipase A2

“…Viperid PLA 2 s show a greater limitation in maintaining their phospholipasic activity when they are submitted to variations in pH and temperature, showing maximum activity only within the narrow range of 35 and 40 C and pHs between 7.0 and 8.0 (Heleno et al, 2013;Huancahuire-Vega et al, 2014). This limitation of activity in function of temperatures and pHs near physiological levels, seems to be characteristic of group II PLA 2 s (viperid) and it is also observed that human PLA 2 s lose stability and activity outside of this range (Leidy et al, 2006).…”