Apoxin I, a novel apoptosis-inducing factor with L-amino acid oxidase activity purified from Western diamondback rattlesnake venom.

Abstract

Venom of the western diamondback rattlesnake (Crotalus atrox) induces apoptosis in human umbilical vein endothelial cells, which could result in hemorrhage in tissues bitten by the snake. To identify the hemorrhagic factor, we purified a novel protein, apoxin I, from rattlesnake venom. Apoxin I induced apoptosis in human umbilical vein endothelial, human promyelocytic leukemia HL-60, human ovarian carcinoma A2780, and mouse endothelial KN-3 cells. Amino acid sequence analysis of the apoxin I showed close similarity to L-amino acid oxidase from the Malayan pit viper (Calloselasma rhodostoma). The purified apoxin I oxidized L-leucine but not D-leucine to produce H2O2. The apoxin I-induced apoptosis was inhibited by catalase, a H2O2 scavenger. These results indicate that the H2O2 produced by L-amino acid oxidation by apoxin I is involved in the apoxin I-induced apoptosis and in hemorrhage caused by rattlesnake venom.

• Authors: S Torii, M Naito, T Tsuruo
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 272 Issue 14 Pg. 9539-42 (Apr 04 1997) ISSN: 0021-9258 [Print] United States
• PMID: 9083096 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antioxidants
• Chromans
• Chromatin
• Crotalid Venoms
• Catalase
• Amino Acid Oxidoreductases
• L-Amino Acid Oxidase
• 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid

Topics

• Amino Acid Oxidoreductases (chemistry, isolation & purification, metabolism)
• Amino Acid Sequence
• Animals
• Antioxidants (pharmacology)
• Apoptosis
• Catalase (metabolism)
• Chromans (pharmacology)
• Chromatin (metabolism)
• Crotalid Venoms (chemistry, isolation & purification, metabolism)
• Crotalus
• HL-60 Cells
• Humans
• L-Amino Acid Oxidase
• Mice
• Molecular Sequence Data
• Molecular Weight