Fig 1.
Isolation and identification of Naja ashei toxins.
A. Anion Exchange Chromatography of fractions C and E obtained from previously performed Size-Exclusion Chromatography of crude Naja ashei venom [11]. B. Protein composition of selected fractions identified by shotgun LC-MS/MS. LAP (Low abundant proteins) – identified proteins whose contribution was less than 1%. Detailed composition of each fraction is available in Supplementary Information (S1 Table).
Fig 2.
Exemplary surface pressure isotherms (π) as a function of the area per lipid molecule (left side) and the relationship between static compression modulus (Cs−1) and surface pressure (π) (right side) obtained for tested Langmuir model membranes after SVMP, CRISP and PLA2 treatment. The control isotherms were obtained for model membranes without toxin fractions exposure.
Fig 3.
Percentage changes calculated for the surface area per molecule, the surface pressure (πcoll) at the moment of monolayer collapse, and the static compressive modulus (Cs−1) obtained for Langmuir model membranes that mimic HL-60 and the SK-N-SH cell lines.Values represent the mean ± SD calculated from 3-5 counts, based on independently recorded isotherms (n = 5). Statistically significant differences between concentrations observed for the SK-N-SH model membranes were indicated by uppercase letters, whereas for the HL-60 membranes, the differences were indicated by lowercase letters.
Fig 4.
Percentage changes in zeta potential of liposomes measured at pH 7.4 after SVMP, CRISP and PLA2 fractions treatment.
The parameter was measured in three biological repetitions and converted into percentage changes in comparison to liposomes without applied fractions. A value of 100% was assigned to the zeta potential of the pure liposomes.
Fig 5.
Membrane integrity disruption measured by lactate dehydrogenase (LDH) release from HL-60 and SK-N-SH cells treated by SVMP, CRISP and PLA2 fractions.
Values represent the average ± SD (n = 5). Different letters indicate significant differences between concentrations (lower case letters for HL-60 cells, uppercase letters for SK-N-SH). The 100% reference value was defined as the enzyme leakage measured in cells that were not exposed to the tested venom proteins.