Venom from the centipede Scolopendra viridis Say: purification, gene cloning and phylogenetic analysis of a phospholipase A2.
Periodo de realización: 1900/01/01 al 2009/01/01
Tipo: Artículo científico
Lugar(es) de estudio: Cuernavaca, Mor., México
Resumen: "Venom components from the centipede Scolopendra viridis Say were studied, using boththe soluble venom and a cDNA library prepared from mRNA of the venomous glands.Separation of the soluble venom by high performance liquid chromatography (HPLC)permitted to obtain at least 54 different fractions. The fraction eluting at 46.24 min showedphospholipase activity. The enzyme was purified to homogeneity and the first 25 aminoacid residues were identified by Edman degradation. From the cDNA library several geneswere cloned, one of which codes for a protein with identical amino acid sequence as theone experimentally determined. The cloned gene codes for a signal peptide of 28 aminoacids and a mature peptide of 119 residues. The molecular weight of the enzyme wasestimated by mass spectrometry and shown to be 13,752 Da, which matches exactly withthe molecular mass expected from the deduced amino acid sequence of the gene. Phylogeneticanalysis of this sequence, in comparison with other known from venomousanimals, showed that it is more similar to snake phospholipases than to insect or arachnidsequences, suggesting that it has been submitted to convergent evolution. To the best ofour knowledge this is the first time that a phospholipase from this species of animal is fullycharacterized. We have named it Scol/Pla."