Long-sarafotoxins: characterization of a new family of endothelin-like peptides.

Sarafotoxins (SRTXs) constitute a family of vasoactive peptides that were initially isolated from the venom of Atractaspis engaddensis, and that are structurally and functionally related to endothelins (ETs). Analysis of the venom of Atractaspis microlepidota microlepidota revealed several new SRTX molecules manifesting some new structural and functional characteristics. These novel SRTXs are longer by three amino acids than the previously described SRTXs, and are designated here "long-SRTXs".

Recovery from sarafotoxin-b induced cardiopathological effects in mice following low energy laser irradiation.

Objective: Low energy laser irradiation has been shown to accelerate various biological processes, including regeneration of injured tissues. In the present work we studied the effect of low energy laser irradiation on ischemic mice hearts, following administration of sarafotoxin-b, a powerful vasoconstrictor peptide of the endothelin/sarafotoxin family.

Methods: Immediately after injection of the toxin and two days later, hearts were exposed to low energy laser irradiation.

Positive Darwinian selection in Vipera palaestinae phospholipase A2 genes is unexpectedly limited to the third exon.

The venom of Vipera palaestinae contains a two-component toxin, consisting of an acidic phospholipase A2 (PLA2) and a basic protein. Here we report the cloning and sequence analysis of the complete V. palaestinae PLA2 genes.

Resistance of the Egyptian mongoose to sarafotoxins.

The Egyptian mongoose (Herpestes ichneumon) is known for its resistance to viperid and elapid venoms. The current work demonstrates that it is also resistant to the venom of Atractaspis and its most toxic component, sarafotoxin-b. Intravenous administration of this toxin, at a dose of about 13 times LD100 for mice, resulted in disturbance in electrocardiograms in the mongoose, which returned to normal after several hours.

Protein and cDNA structures of an acidic phospholipase A2, the enzymatic part of an unusual, two-component toxin from Vipera palaestinae.

In the venom of Vipera palaestinae an unusual, two-component toxin was found. The two components of the toxin are an acidic phospholipase A2 (VpaPLA2) and a basic protein, both with an apparent molecular mass of about 15 kDa. Each component alone is not toxic; however, their mixture is lethal.