Molecular cloning and characterization of ecto-5'-nucleotidase from the venoms of Gloydius blomhoffi.

A Gloydius blomhoffi brevicaudus venom gland cDNA library was screened to isolate cDNA clones using probes based on highly conserved amino acid sequences from known ecto-5'-nucleotidases (ecto-5'-NTs). Molecular cloning of ecto-5'-NT from G. blomhoffi brevicaudus venom predicted that it was a glycosyl phosphatidylinositol-anchored membrane protein containing 588 amino acid residues with 7 potential N-linked glycosylation sites.

Characterization and cDNA cloning of aminopeptidase A from the venom of Gloydius blomhoffi brevicaudus.

The aminopeptidase activities of snake venoms from Gloydius blomhoffi brevicaudus, Gloydius halys blomhoffii, Trimeresurus flavoviridis, Bothrops jararaca and Crotalus atrox were investigated. Aminopeptidase A (APA), aminopeptidase B and aminopeptidase N activities were present in all snake venoms. The strongest APA activity was found in venom from G.

A novel peptide from the ACEI/BPP-CNP precursor in the venom of Crotalus durissus collilineatus.

In crotaline venoms, angiotensin-converting enzyme inhibitors [ACEIs, also known as bradykinin potentiating peptides (BPPs)], are products of a gene coding for an ACEI/BPP-C-type natriuretic peptide (CNP) precursor. In the genes from Bothrops jararaca and Gloydius blomhoffii, ACEI/BPP sequences are repeated. Sequencing of a cDNA clone from venom glands of Crotalus durissus collilineatus showed that two ACEIs/BPPs are located together at the N-terminus, but without repeats.

Characterization and cDNA cloning of dipeptidyl peptidase IV from the venom of Gloydius blomhoffi brevicaudus.

Dipeptidyl peptidase activity was investigated in snake venoms from Gloydius blomhoffi brevicaudus, Gloydius halys blomhoffii, Trimeresurus flavoviridis and Crotalus atrox. The strongest dipeptidyl peptidase IV (DPP IV) activity was found in venom from G. blomhoffi brevicaudus.

Molecular cloning of the major lethal toxins from two kraits (Bungarus flaviceps and Bungarus candidus).

The major lethal toxins present in the venoms of the red-headed krait, Bungarus flaviceps, and the Malayan krait, Bungarus candidus, have both been purified. Each consists of two polypeptide chains, A and B, joined by a disulfide bond. In the present study, primary structures of these toxins were determined by Edman degradation and by nucleotide sequencing of the cDNA clones.

Molecular cloning of serine proteinases from Bothrops jararaca venom gland.

Snake venom is known to contain an abundance of enzyme isoforms, and various disorders associated with envenomation have been ascribed partially to their diversified functions. Crude venom of Bothrops jararaca was subjected to conventional two-dimensional SDS-PAGE, followed by immunoblot analysis using an antiserum raised against KN-BJ 2, a serine proteinase previously isolated from this venom. A number of immunoreactive proteins with comparable molecular masses and different pIs emerged, implying the venom contains yet-unknown serine proteinases.

Identification of multiple cytochrome P450 genes belonging to the CYP4 family in Xenopus laevis: cDNA cloning of CYP4F42 and CYP4V4.

In order to obtain cDNA clones coding for CYP4 proteins in frog Xenopus laevis, degenerate primers were designed utilizing the conserved sequences of known CYP4s and were used to amplify partial cDNA fragments from liver mRNA. Five new CYP genes were identified. Three of these genes, XL-1, -2 and -3, were assigned to the CYP4T subfamily found previously in fish and amphibians.

The unusual high molecular mass of Bothrops protease A, a trypsin-like serine peptidase from the venom of Bothrops jararaca, is due to its high carbohydrate content.

Bothrops protease A (BPA) is a serine peptidase isolated from the venom of Bothrops jararaca. Unlike many venom enzymes, it is stable at pHs between 3 and 9 and resists heating at 86 degrees C for 10 min. Mature snake venom serine peptidases of the chymotrypsin family are in general glycoproteins composed of around 232 amino acids and their molecular masses vary between 25 and 40 kDa.

Molecular cloning and expression analysis of the aryl hydrocarbon receptor of Xenopus laevis.

The aryl hydrocarbon receptor (AHR) is a member of the basic helix-loop-helix/Per-Arnt-Sim (bHLH/PAS) family of transcription factors. Although this receptor has been known to mediate the toxic effects of environmental pollutants, its physiological functions remain elusive. Here, we describe the isolation and expression pattern of the Xenopus AHR gene.