| Affiliation: | (1) Department of Pharmacology, School of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil;(2) Department of Physiology and Biophysics, Institute of Biology, State University of Campinas, (UNICAMP), Campinas, SP, Brazil;(3) Department of Biochemistry, Institute of Biology, State University of Campinas, (UNICAMP), Campinas, SP, Brazil;(4) Department of Biochemistry and Molecular Biology, Federal University of Ceará (UFC), Fortaleza, Ceará, Brazil |
| Abstract: | A new Phospholipase A2 (PLA2) from Micrurus dumerilii carinicauda venom was isolated and its primary structure determined. This new PLA2 showed a low enzymatic activity when compared with other PLA2s and it is moderately basic with an isoelectric point of 8.0. Its amino acid sequence showed the presence of 120 amino acid residues and its sequence was: NLIQFLNMIQCTTPGREPLVAFANYGCYCGRGGSGTPVDELDRCCQVHDNCYDTAKKVFGCSPYFTMYSYDCSEGKLTCKDNNTKCKAAVCNCDRTAALCFAKAPYNDKNYKIDLTKRCQ. The structural model of MIDCA1, when compared with other strong neurotoxic PLA2s, such as Naja naja, showed significant differences in the β-wing and neurotoxic sites, despite the high level of amino acid sequence similarity. These observations indicate a dissociation between the biological and catalytic activity of this new PLA2, supporting the view that other regions of the protein are involved in the biological effects. |
