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6ax2

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Solution structure of Magi3 a specific insect toxin from the spider Macrothele gigas

Structural highlights

6ax2 is a 1 chain structure with sequence from Macrothele gigas. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Solution NMR, 12 models
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

TX22A_MACGS Competes for binding at site 3 of the insect voltage-gated sodium channel (Nav) (PubMed:12860384). Insecticidal neurotoxin (PubMed:12860384, PubMed:29247580). Causes temporary paralysis to lepidopteran larvae (10.3 nmol/g) or to crickets (doses from 0.93 to 119 ug/g) (PubMed:12860384, PubMed:29247580). Is not toxic to mice when injected intracranially (high doses) (PubMed:12860384, PubMed:29247580).^[1] ^[2]

Publication Abstract from PubMed

The need for molecules with high specificity against noxious insects leads the search towards spider venoms that have evolved highly selective toxins for insect preys. In this respect, spiders as a highly diversified group of almost exclusive insect predators appear to possess infinite potential for the discovery of novel insect-selective toxins. In 2003, a group of toxins was isolated from the spider Macrothele gigas and the amino acid sequence was reported. We obtained, by molecular biology techniques in a heterologous system, one of these toxins. Purification process was optimized by chromatographic methods to determine the three-dimensional structure by nuclear magnetic resonance in solution, and, finally, their biological activity was tested. rMagi3 resulted to be a specific insect toxin with no effect on mice.

Successful refolding and NMR structure of rMagi3: a disulfide-rich insecticidal spider toxin.,Titaux-Delgado G, Carrillo E, Mendoza A, Mayorga-Flores M, Escobedo-Gonzalez FC, Cano-Sanchez P, Lopez-Vera E, Corzo G, Del Rio-Portilla F Protein Sci. 2017 Dec 16. doi: 10.1002/pro.3363. PMID:29247580^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Corzo G, Gilles N, Satake H, Villegas E, Dai L, Nakajima T, Haupt J. Distinct primary structures of the major peptide toxins from the venom of the spider Macrothele gigas that bind to sites 3 and 4 in the sodium channel. FEBS Lett. 2003 Jul 17;547(1-3):43-50. PMID:12860384
↑ Titaux-Delgado G, Carrillo E, Mendoza A, Mayorga-Flores M, Escobedo-Gonzalez FC, Cano-Sanchez P, Lopez-Vera E, Corzo G, Del Rio-Portilla F. Successful refolding and NMR structure of rMagi3: a disulfide-rich insecticidal spider toxin. Protein Sci. 2017 Dec 16. doi: 10.1002/pro.3363. PMID:29247580 doi:http://dx.doi.org/10.1002/pro.3363
↑ Titaux-Delgado G, Carrillo E, Mendoza A, Mayorga-Flores M, Escobedo-Gonzalez FC, Cano-Sanchez P, Lopez-Vera E, Corzo G, Del Rio-Portilla F. Successful refolding and NMR structure of rMagi3: a disulfide-rich insecticidal spider toxin. Protein Sci. 2017 Dec 16. doi: 10.1002/pro.3363. PMID:29247580 doi:http://dx.doi.org/10.1002/pro.3363