Antimicrobial activity of myotoxic phospholipases A2 from crotalid snake venoms and synthetic peptide variants derived from their C-terminal region

Bactericidal and Antiendotoxic Properties of Short Cationic Peptides Derived from a Snake Venom Lys49 Phospholipase A2

“…Such an enhancement of the bactericidal effect of p115-W3 was confirmed in the present study with a broader range of bacteria, including both grampositive and gram-negative species, as well as Brucella spp., which are known to be highly resistant to cationic peptides (9,26). Nevertheless, due to the high degree of toxicity of p115-W3, a series of modifications were examined for their effects on the bactericidal and cytolytic potencies of the peptides (32). From such analyses, pEM-2, a modified synthetic peptide, was selected for further characterization.…”

“…‫,ء‬ statistically significant difference (P Ͻ 0.05) between LPS alone and pEM-2 (D). N-terminal hydrophobic segment of p115-W3, which contains the tryptophan cluster, is replaced by the same cationic sequence of its C-terminal half (KKALAKLKALAKK), the peptide loses all bactericidal activity (32).…”

“…Such studies identified a peptide variant, named pEM-2, as an interesting candidate for further evaluation of its antimicrobial potential (32). Therefore, in the present investigation, the bactericidal activities and antiendotoxic properties of synthetic pEM-2 in both its L-and D-enantiomeric forms were characterized in vitro and in vivo.…”

Novel phospholipase A2 inhibitors from python serum are potent peptide antibiotics

“…In particular, many of the myotoxic snake venom (sv) PLA 2 s possess bactericidal activity based on common effects of group II PLA 2 s [44]. Bactericidal effects of Porthidium nasutum phospholipase A 2 (PnPLA 2 ) occur against S. aureus but not Escherichia coli at a 32 mg/ml dose [45].…”

“…However, another study shows that catalytically-inactive PLA 2 homologues also can possess antibacterial activity [49e52], localized within the C-terminal region. As an example, the C-terminal peptide (115e129) of myotoxin II from B. asper venom reproduces the antimicrobial activity of the native protein against bacteria [44]. The effects of sPLA 2 s on Gram-positive and Gram-negative bacteria depend on factors that disrupt their outer membranes.…”