Novel lynx spider toxin shares common molecular architecture with defense peptides from frog skin.Dubovskii, P.V., Vassilevski, A.A., Samsonova, O.V., Egorova, N.S., Kozlov, S.A., Feofanov, A.V., Arseniev, A.S., Grishin, E.V.
(2011) Febs J. 278: 4382-4393
- PubMed: 21933345
- DOI: 10.1111/j.1742-4658.2011.08361.x
- PubMed Abstract:
A unique 30-residue cationic peptide oxyopinin 4a (Oxt 4a) was identified in the venom of the lynx spider Oxyopes takobius (Oxyopidae). Oxt 4a contains a single N-terminally located disulfide bond, Cys4-Cys10, and is structurally different from any s ...
A unique 30-residue cationic peptide oxyopinin 4a (Oxt 4a) was identified in the venom of the lynx spider Oxyopes takobius (Oxyopidae). Oxt 4a contains a single N-terminally located disulfide bond, Cys4-Cys10, and is structurally different from any spider toxin studied so far. According to NMR findings, the peptide is disordered in water, but assumes a peculiar torpedo-like structure in detergent micelles. It features a C-terminal amphipathic α-helical segment (body; residues 12-25) and an N-terminal disulfide-stabilized loop (head; residues 1-11), and has an unusually high density of positive charge in the head region. Synthetic Oxt 4a was produced and shown to possess strong and broad-spectrum cytolytic and antimicrobial activity. cDNA cloning showed that the peptide is synthesized in the form of a conventional prepropeptide with an acidic prosequence. Unlike other arachnid toxins, Oxt 4a exhibits striking similarity with defense peptides from the skin of ranid frogs that contain the so-called Rana-box motif (a C-terminal disulfide-enclosed loop). Parallelism or convergence is apparent on several levels: the structure, function and biosynthesis of a lynx spider toxin are mirrored by those of Rana-box peptides from frogs.
M M Shemyakin and Yu A Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia. firstname.lastname@example.org