Cn2 toxin

Cn2 toxin is a single chain β-scorpion neurotoxic peptide and the primary toxin in the venom of the Centruroides noxious Hoffmann scorpion.Cn2 is a neurotoxin named after and derived from the Centruroides noxious scorpion, which originates from and is endemic in the state of Nayarit, Western Mexico. This scorpion produces a venom in which the Cn2 toxin is the most abundant component; it comprises approximately 6.8% of the scorpion venom. Cn2 toxin is one of the most noxious peptides against mammals. Cn2 is initially purified and sequenced under the name of toxin II.9.2.2.The Cn2 toxin comprises a triple-stranded antiparallel β-sheet, a short α-helix, and four disulfide bridges. Two of these disulfide bridges contribute to maintaining the relative position of one of the β-sheet and α-helix. The third disulfide bridge binds the long loop between the first β-sheet and α-helix to the C-terminus, while the fourth binds this loop to the third β-sheet. The Cn2 peptide contains many aromatic residues: seven tyrosine residues, two tryptophan residues and one phenylalanine residue. These residues form two hydrophobic patches, a hydrophobic core, two positive patches, and a negative patch in the protein, which have been extensively described