Mechanisms of cell death induction by L-amino acid oxidase, a major component of ophidian venom.
L-amino acid oxidase (LAAO) from the Malayan pit viper induces both necrosis and apoptosis in Jurkat cells. Cell death by necrosis is attributed to H2O2 produced by oxidation of alpha-amino acids. In the presence of catalase that effectively scavenges H2O2, a switch to apoptosis is observed. The major factors contributing to apoptosis are proposed to be: (i) generation of toxic intermediates from fetal calf serum (ii) binding and internalization of LAAO. The latter process appears to be mediated by the glycan moiety of the enzyme as desialylation reduces cytotoxicity. D-amino acid oxidase (DAAO), which catalyzes the same reaction as LAAO but lacks glycosylation, triggers necrosis as a consequence of H2O2 production but not apoptosis in the presence of catalase. Thus induction of cell death by LAAO appears to involve both the generation of H2O2 and the molecular interaction of the glycan moiety of the enzyme with structures at the cell surface.
Ande
Sudharsana Rao
SR
Biochemistry Research Group, University of Konstanz, D-78464 Konstanz, Germany.
Kommoju
Phaneeswara Rao
PR
Draxl
Sigrid
S
Murkovic
Michael
M
Macheroux
Peter
P
Ghisla
Sandro
S
Ferrando-May
Elisa
E
D000601:Amino Acids, Essential / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002374:Catalase; D002417:Cattle / Q000097:blood; D016923:Cell Death / Q000187:drug effects*; D003435:Crotalid Venoms / Q000201:enzymology; D003605:D-Amino-Acid Oxidase / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D019169:Jurkat Cells / Q000187:drug effects; D050830:L-Amino Acid Oxidase / Q000378:metabolism* / Q000494:pharmacology; D019158:N-Acetylneuraminic Acid / Q000502:physiology; D009336:Necrosis / Q000139:chemically induced
D000601:Amino Acids, Essential; D003435:Crotalid Venoms; D006861:Hydrogen Peroxide; D002374:Catalase; D050830:L-Amino Acid Oxidase; D003605:D-Amino-Acid Oxidase; D019158:N-Acetylneuraminic Acid