RESUMO
Hyaluronidases (Hyal) present in the venom of poisonous animals have been considered as "spreading factors" that facilitate a fast penetration of the venom in the prey. We have found that hyaluronidase from the tarantula Brachypelma vagans venom (BvHyal) displays a substrate-specific Hyal activity against hyaluronan. By using a combined strategy based on peptide sequencing and RT-PCR, we have cloned a BvHyal cDNA. Active recombinant BvHyal was efficiently expressed in a baculovirus system in insect cell.
Assuntos
Hialuronoglucosaminidase/genética , Venenos de Aranha/enzimologia , Animais , Baculoviridae/genética , Clonagem Molecular , Hialuronoglucosaminidase/química , Insetos , Proteínas Recombinantes/biossínteseRESUMO
In this study we report the isolation and characterization of several sphingomyelinase D isoforms from the venoms of the North American spiders Loxosceles boneti and Loxosceles reclusa, from Mexico and the United States, respectively. We have measured their enzymatic activity, their capacity to induce necrotic lesions in rabbits, cloned the cDNAs coding for the mature forms of two of the isoforms from L. boneti and two of L. reclusa based on N-terminal sequence information of the purified proteins, and performed a comprehensive comparison of the sequence data generated by us with that reported for other sphingomyelinase genes to date.
Assuntos
Isoenzimas/genética , Diester Fosfórico Hidrolases/genética , Venenos de Aranha/química , Aranhas/enzimologia , Animais , Clonagem Molecular , DNA Complementar/biossíntese , DNA Complementar/genética , Isoenzimas/metabolismo , Dados de Sequência Molecular , Necrose , América do Norte , Diester Fosfórico Hidrolases/isolamento & purificação , Diester Fosfórico Hidrolases/metabolismo , Coelhos , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Venenos de Aranha/genética , Aranhas/genética , Aranhas/metabolismoRESUMO
A comparison of some components of the venoms of two Costa Rican tarantulas, Aphonopelma seeamanni (Cambridge) and Sphaerobothria hoffmanni (Karsch) by polyacrylamide gel electrophoresis shows patterns similar to those of Dugesiella hentzi (Girard), a North American tarantula. The digestive secretions have proteins that do not enter the 15% gels; thus no bands are obsorved. The method used by the tarantulas to consume their prey involves the action of both the venom and the digestive secretions. The percent protein, pH, proteolytic activity and hemolytic activity of venom and digestive secretions of both species were determined, and a high proteolytic activity for digestive secretions was found.