Purification, amino-acid sequence and partial characterization of two toxins with anti-insect activity from the venom of the South American scorpion Tityus bahiensis (Buthidae).

Submitted by Karine Ribeiro (karinelg.ribeiro@gmail.com) on 2015-03-02T17:56:47Z No. of bitstreams: 1 ARTIGO_PurficationAminoSequence.pdf: 660407 bytes, checksum: 97c253779e109038ed65eda87bc0fcc9 (MD5)Approved for entry into archive by Oliveira Flávia (flavia@sisbin.ufop.br) on 2015-03-02T18:51:02Z (GMT) No. of bitstreams: 1 ARTIGO_PurficationAminoSequence.pdf: 660407 bytes, checksum: 97c253779e109038ed65eda87bc0fcc9 (MD5)Made available in DSpace on 2015-03-12T18:54:27Z (GMT). No. of bitstreams: 1 ARTIGO_PurficationAminoSequence.pdf: 660407 bytes, checksum: 97c253779e109038ed65eda87bc0fcc9 (MD5) Previous issue date: 2001We report here the isolation by a two-step chromatographic procedure of two new toxins from the South American scorpion Tityus bahiensis. Their amino-acid sequences and some of their biological features were established. The two toxins have different biological properties. Toxin TbIT-I had almost no activity or pharmacological effects in vertebrate tissues whereas it was lethal to house ¯ies (LD50 80.0 ng/house ¯y). In contrast, Tb2-II was active against both mammals (intracerebroventricular injection of 100 ng/mouse was lethal) and insects (LD50 40.0 ng/house ¯y). The amino-acid sequences of these toxins were established and found to be similar (60±95%) to previously described b-toxins from the Tityus genus. Based on the available comparative information, this study attempts identify possible structure±function relationships that may be responsible for the differences in bioactivity displayed by these toxins