Cobra Cytotoxins: Structural Organization and Antibacterial Activity

Abstract

Cardiotoxins (cytotoxins, CT) are β-structured proteins isolated from the venom of cobra. They consist of 59–61 amino acid residues, whose antiparallel chains form three ‘fingers’. In contrast to neurotoxins with an overall similar fold, CTs are amphiphilic. The amphiphilicity is caused by positively charged lysine and arginine residues flanking the tips of the loops that consist primarily of hydrophobic amino acids. A similar distribution of amino acid residues is typical for linear (without disulfide bonds) cationic cytolytic peptides from the venoms of other snakes and insects. Many of them are now considered to be lead compounds in combatting bacterial infections and cancer. In the present review, we summarize the data on the antibacterial activity of CTs and compare it to the activity of linear peptides.

Latarcins: versatile spider venom peptides

“…Indeed, the respective correlation coefficients are negative (Table 5). It is interesting to note that similar conclusions were drawn for CT The following LP were taken into account: Ltc 1, 2a, 3a, 3b, 4a, 4b, 5, 6a, and 7, nine molecules in total Antibacterial activity is assumed to be a value reciprocal to MIC, and the values of MIC were taken from [28] a Full charge at pH 7 (as reported in Table 1) b The number of positively charged residues (Arg and Lys, reported in Table 1) c The result is obtained taking into account only the number of negatively charged residues d In the DG scale (see details in Table 3) e In the DG scale (the values in the brackets correspond to the conditions of protonation of Asp, Glu, and His residues) f Hydrophobicity was assumed to be the value proportional to the reciprocal of the concentration of AMP necessary to disrupt planar membranes composed from DPhPC; see Table 3 for the values [108,112] and linear AMP of different origin [113,114]. Of note, for LP an optimal charge, required to reach the maximal antimicrobial effect, depends on the overall length of the peptide [115,116] and distribution of charged residues along the amino acid sequence [37].…”

Bothrops jararaca and Bothrops erythromelas Snake Venoms Promote Cell Cycle Arrest and Induce Apoptosis via the Mitochondrial Depolarization of Cervical Cancer Cells

“…Some approaches with snake venoms have been of great importance in the presentation of anti-inflammatory activity [16], antibacterial activity [17], and antiparasitic activity against Leishmania [18], making it a natural source of interest to cancer therapy [19, 20]. Previous trials have reported that snake venoms are able to act on the tumor in some models, such as melanoma (B16F10 cells) [21], breast (MCF-7 cells) [22], colon (HCT116 and HT-29 cells) [23], lung cancer (NCL-H460 cells) [24], and neuroblastoma (SK-N-MC and SK-N-SH cells) [25].…”

An Appraisal of Antidotes’ Effectiveness: Evidence of the Use of Phyto-Antidotes and Biotechnological Advancements

“…The ability of snake venom cytotoxins to kill cells and tissues have been said to be a valuable property in the treatment of tumour cells [84] as well as cancer [83], for example, ACTX-8 isolated from the venom of Agkistrodon acutus caused apoptosis in Hela cervical cancer cells [85]. Cytotoxins are basically toxic β-structured proteins consisting of 59-61 amino acid residues and they constitute about 40%-70% of the venom of cobra snakes in the genus Naja and Haemachatus [86]. Haemachatus are found mainly in Africa, distributed across South Africa, Swaziland and some parts of Mozambique and Zimbabwe.…”