Isolation and chemical characterization of PwTx-II: A novel alkaloid toxin from the venom of the spider Parawixia bistriata (Araneidae, Araneae)

• Published in: Toxicon (Oxford) Vol. 46; no. 7; pp. 786 - 796
• Main Authors: Cesar, Lilian M.M., Mendes, Maria A., Tormena, Claudio F., Marques, Maurício R., de Souza, Bibiana M., Saidemberg, Daniel Menezes, Bittencourt, Jackson C., Palma, Mario S.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2005; Elsevier Science
• Subjects: Alkaloid; Animal poisons toxicology. Antivenoms; Animals; Apis mellifera; Araneae; Araneidae; Biological and medical sciences; Carbolines - chemistry; Carbolines - isolation & purification; Carbolines - toxicity; Dose-Response Relationship, Drug; Lethal Dose 50; Male; Medical sciences; Molecular Structure; Natural compound; Natural product; Neurotoxicity; Parawixia bistriata; Rats; Rats, Wistar; Seizures - chemically induced; Spectroscopy; Spider toxin; Spider venom; Spider Venoms - chemistry; Spider Venoms - isolation & purification; Spider Venoms - toxicity; Spiders - chemistry; Structure determination; Toxicology; Toxins, Biological - chemistry; Toxins, Biological - isolation & purification; Toxins, Biological - toxicity; Spectroscopy; Alkaloid; Neurotoxicity; Spider toxin; Natural product; Spider venom; Natural compound; Structure determination; Nervous system diseases; Toxicity; Chemical compound; Animal origin; Araneida; Characterization; Toxin; Arachnida; Alkaloid; Structure determination; Neurotoxicity; Natural product; Spectroscopy; Spider venom; Spider toxin; Natural compound; Arthropoda; Venom; Isolation; Invertebrata; Araneidae; Structural analysis
• ISSN: 0041-0101; 1879-3150
• DOI: 10.1016/j.toxicon.2005.08.005

Brazil has many species of spiders belonging to Araneidae family however, very little is known about the composition, chemical structure and mechanisms of action of the main venom components of these spiders. The main objective of this work was to isolate and to perform the chemical characterization of a novel β-carboline toxin from the venom of the spider Parawixia bistriata, a typical species of the Brazilian ‘cerrado’. The toxin was purified by RP-HPLC and structurally elucidated by using a combination of different spectroscopic techniques (UV, ESI-MS/MS and 1H NMR), which permitted the assignment of the molecular structure of a novel spider venom toxin, identified as 1-4-guanidinobutoxy-6-hydroxy-1,2,3,4-tetrahydro-β-carboline, and referred to here as PwTx-II. This compound is toxic to insects (LD 50=12±3 ηg/mg honeybee), neurotoxic, convulsive and lethal to rats (LD 50=9.75 mg/kg of male Wistar rat).