title: L-amino acid oxidase activity of an antineoplastic factor of a marine mollusk and its relationship to cytotoxicity.
abstract: Dolabellanin A (DAA), an antineoplastic protein of an ocean mollusk, was shown to have L-amino acid oxidase (LAAO, EC 1.4.3.2) activity. With the addition of DAA, a cytotoxic concentration of hydrogen peroxide was detected in the culture medium of EL-4 murine lymphoma cells. The cytotoxicity of DAA was suppressed by antioxidants, especially by catalase. The hydrogen peroxide produced by the LAAO activity was recognized to be involved in the cytotoxicity, and the cell death seemed to be due to the direct toxicity of this substance. However, the cytotoxicity of a higher concentration of DAA was only partially suppressed even when an excess amount of catalase was used. A portion of the cells that died showed features of apoptosis such as increased caspase 3 activity and DNA fragmentation. This indicated that apoptosis was induced by DAA activity but independently of the direct toxicity of hydrogen peroxide.
authors.affiliation: Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Tsukui-gun, Kanagawa 199-0195, Japan. ryo-iiji@pharm.teikyo-u.ac.jp
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Iijima
authors.forename: Jun
authors.initials: J
authors.lastname: Kisugi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yamazaki
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000378:metabolism*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D006023:Glycoproteins / Q000494:pharmacology*; D050830:L-Amino Acid Oxidase; D008223:Lymphoma / Q000188:drug therapy*; D051379:Mice; D008974:Mollusca / Q000201:enzymology*
chemical_list: D000970:Antineoplastic Agents; D006023:Glycoproteins; C063649:dolabellanin A protein, Dolabella auricularia; D000594:Amino Acid Oxidoreductases; D050830:L-Amino Acid Oxidase