Isolation and characterization of an apoptotic and platelet aggregation inhibiting L-amino acid oxidase from Vipera berus berus (common viper) venom.
An L-amino acid oxidase was isolated from the venom of the common viper Vipera berus berus by a three-step procedure combining gel filtration, ion exchange and hydrophobic chromatography. The enzyme is a non-covalently bound homodimer with a monomeric molecular mass of 57.7 kDa. The N-terminal amino acid sequence and the internal peptide sequences show close structural homology with other snake venom L-amino acid oxidases. The purified protein catalyzed oxidative desamination of L-amino acids, the most specific substrate is L-Phe. The best substrates among the studied 20 amino acids were: L-Met, L-Leu, L-Phe, L-Ile, L-Arg and L-His. Five amino acids, L-Ser, L-Pro, Gly, L-Thr and L-Cys, were not oxidized. The enzyme inhibited ADP-induced platelet aggregation dose-dependently with an IC50 of 0.07 microM. The effect was neutralized by catalase. V. berus berus LAAO induced apoptosis in cultured HeLa and K562 cells as shown by DNA fragmentation gel pattern. The induction of apoptosis was inhibited by catalase.
National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia.
Mari
M
Samel
Heiki
H
Vija
Gunilla
G
Rönnholm
Jüri
J
Siigur
Nisse
N
Kalkkinen
Ene
E
Siigur
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D053938:DNA Fragmentation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D050830:L-Amino Acid Oxidase / Q000302:isolation & purification* / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D014757:Viper Venoms / Q000201:enzymology*
D010975:Platelet Aggregation Inhibitors; D014757:Viper Venoms; D050830:L-Amino Acid Oxidase