title: L-amino acid oxidase from Trimeresurus jerdonii snake venom: purification, characterization, platelet aggregation-inducing and antibacterial effects.
abstract: An L-amino acid oxidase (LAO), designated as TJ-LAO, was purified to homogeneity from the venom of Trimeresurus jerdonii by Sephadex G-100 and Q Sepharose HP chromatography. The molecular weight of this enzyme was 110 kD as estimated by analytical gel filtration and was 55 kD by SDS-polyacrylamide gel electrophoresis, suggesting that the enzyme is composed of two subunits. The enzyme has an absorption spectrum characteristic of flavoproteins, containing 2 moles of FMN per mole of enzyme. The N-terminal sequence of TJ-LAO shares high homology with other viperid snake venom LAOs. Homology with elapid venom LAO is lower. TJ-LAO inhibited the growth of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus megaterium. The antibacterial effect associated with LAO activity was elminated with the addition of catalase. Platelets in platelet-rich plasma aggregated upon the addition of TJ-LAO. The enzyme-induced aggregation was inhibited by catalase, suggesting formation of H2O2 was essential for TJ-LAO to induce platelet aggregation. These results showed H2O2 formation is important for the biological effects of LAO.
authors.affiliation: Department of Animal Toxinology, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, Yunnan, China.
authors.forename: Qiu-Min
authors.initials: QM
authors.lastname: Lu
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
authors.forename: Yang
authors.initials: Y
authors.lastname: Jin
authors.forename: Ji-Fu
authors.initials: JF
authors.lastname: Wei
authors.forename: Wan-Yu
authors.initials: WY
authors.lastname: Wang
authors.forename: Yu-Liang
authors.initials: YL
authors.lastname: Xiong
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D003435:Crotalid Venoms / Q000201:enzymology*; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D050830:L-Amino Acid Oxidase; D008969:Molecular Sequence Data; D010974:Platelet Aggregation / Q000187:drug effects; D011817:Rabbits; D017386:Sequence Homology, Amino Acid
chemical_list: D000900:Anti-Bacterial Agents; D003435:Crotalid Venoms; C029748:Trimeresurus venoms; D000594:Amino Acid Oxidoreductases; D050830:L-Amino Acid Oxidase