Effect of dimerized melittin on gastric cancer cells and antibacterial activity.

Melittin is the peptide toxin found in bee venom and is effective against cancer cells. To enhance its activity, a branched dimeric form of melittin was designed. The monomeric form of the peptide was more cytotoxic against gastric cancer cells at low concentrations (1-5 μM) than the dimer form, while the cytotoxic effect was comparable at higher concentrations (10 μM).

L-amino acid oxidase from snake venom and its anticancer potential.

L-amino acid oxidase (LAAO) is a protein toxin commonly found in snake venom. It has many applications, ranging from biotechnology to potential anticancer therapeutics. LAAO converts L-amino acid into α-keto acid and release ammonia and hydrogen peroxide as by-products.

Role of individual disulfide bridges in the conformation and activity of spinoxin (α-KTx6.13), a potassium channel toxin from Heterometrus spinifer scorpion venom.

Spinoxin (SPX; α-KTx6.13), isolated from venom of the scorpion Heterometrus spinifer, is a K channel-specific peptide toxin (KTx), which adopts a cysteine-stabilized α/β scaffold that is cross-linked by four disulfide bridges (Cys1-Cys5, Cys2-Cys6, Cys3-Cys7, and Cys4-Cys8). To investigate the role of the individual disulfide bonds in the structure-activity relationship of SPX, we synthesized four SPX analogs in which each pair of cysteine residues was replaced by alanine residues.

Active Sites of Spinoxin, a Potassium Channel Scorpion Toxin, Elucidated by Systematic Alanine Scanning.

Peptide toxins from scorpion venoms constitute the largest group of toxins that target the voltage-gated potassium channel (Kv). Spinoxin (SPX) isolated from the venom of scorpion Heterometrus spinifer is a 34-residue peptide neurotoxin cross-linked by four disulfide bridges. SPX is a potent inhibitor of Kv1.

Scorpion venoms as a potential source of novel cancer therapeutic compounds.

Scorpions and their venoms have been used in traditional medicine for thousands of years in China, India and Africa. The scorpion venom is a highly complex mixture of salts, nucleotides, biogenic amines, enzymes, mucoproteins, as well as peptides and proteins (e.g.