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Elapid venom toxins: multiple recruitments of ancient scaffolds
- Source :
- European Journal of Biochemistry; Volumen 259, Número 1-2. 1999, Kérwá, Universidad de Costa Rica, instacron:UCR
- Publication Year :
- 1999
-
Abstract
- Nigroxins A and B, two myotoxic phospholipases A2 (PLA2s) from the venom of the American elapid Micrurus nigrocinctus, belong to a new PLA2 subclass. Their primary structures were established and compared with those of PLA2s that have already been studied with respect to myotoxic activity. The combination of amino acid residues Arg15, Ala100, Asn108 and a hydrophobic residue at position 109 is present exclusively in class I PLA2s that display myotoxic activity. These residues cluster within a surface region rich in positive charges and are suggested to play a role in the interaction with the target membrane of the muscle fibers. It is concluded that the myotoxic PLA2s resulted from recruitment of an ancient scaffold. Dendrotoxins and alpha-neurotoxins are similarly derived from other old structures, which are, however, now also present in nontoxic proteins that are widely distributed throughout the animal kingdom. The evolutionary pathways by which elapid PLA2s acquired myotoxicity and dendrotoxins acquired K+-channel blocker activity are traced. They demonstrate how existing scaffolds were adapted stepwise to serve toxic functions by exchange of a few surface-exposed residues. Universidad de Costa Rica//UCR/Costa Rica Swedish Agency for Research Cooperation with Developing Countries//SAREC/Suecia Swedish Medical Research Council///Suecia Commission of the European Union/[BIO4-CT97-2123]// UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)
- Subjects :
- Models, Molecular
Protein family
Structural Comparisons
Myotoxin
Molecular Sequence Data
Venom
Reptilian Proteins
Phospholipase
Cross Reactions
Biochemistry
Subclass
Phospholipases A
Toxic Site
Toxicology
Evolution, Molecular
Mice
Structure-Activity Relationship
Phospholipase A2
Protein Evolution
Micrurus nigrocinctus
Protein Family
Animals
Cluster Analysis
Protease Inhibitors
Amino Acid Sequence
Elapidae
Group I Phospholipases A2
Muscle, Skeletal
Conserved Sequence
Toxins, Biological
Elapid Venoms
biology
Sequence Homology, Amino Acid
biology.organism_classification
Phospholipases A2
Hydrophobic residue
biology.protein
lipids (amino acids, peptides, and proteins)
Peptides
Subjects
Details
- ISSN :
- 00142956
- Volume :
- 259
- Issue :
- 1-2
- Database :
- OpenAIRE
- Journal :
- European journal of biochemistry
- Accession number :
- edsair.doi.dedup.....ba6b50d1bbf991d697c43c5a541de2e2