Enzymatic nitration of phytophenolics: evidence for peroxynitrite‐independent nitration of plant secondary metabolites

FEBS Letters

Yamasaki, Hideo³  Ichiba, Toshio¹  Fukushi, Yukiharu²  Sakihama, Yasuko³  Tamaki, Ryoko³  Tahara, Satoshi²  Shimoji, Hisashi³ 

[1] Research and Development Division, Okinawa Industrial Technology Center (OITC), 12-2 Suzaki, Gushikawa, Okinawa 904-2234, Japan;Laboratory of Ecological Chemistry, Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo 060-8589, Japan;Laboratory of Cell and Functional Biology, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa 903-0213, Japan

关键词: Horseradish peroxidase;    Nitric oxide;    Nitrite;    Peroxynitrite;    Plant phenolics;    Reactive nitrogen species;    HRP;    horseradish peroxidase;    HCA;    hydroxycinnamic acid;    NO;    nitric oxide;    NO2•;    nitrogen dioxide radical;    ONOO−;    peroxynitrite;    p-CA;    p-coumaric acid;    RNS;    reactive nitrogen species;   

DOI  :  10.1016/S0014-5793(03)01059-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Peroxynitrite (ONOO⁻), a reactive nitrogen species, is capable of nitrating tyrosine residue of proteins. Here we show in vitro evidence that plant phenolic compounds can also be nitrated by an ONOO⁻-independent mechanism. In the presence of NaNO₂, H₂O₂, and horseradish peroxidase (HRP), monophenolic p-coumaric acid (p-CA, 4-hydroxycinnamic acid) was nitrated to form 4-hydroxy-3-nitrocinnamic acid. The reaction was completely inhibited by KCN, an inhibitor for HRP. The antioxidant ascorbate suppressed p-CA nitration and its suppression time depended strongly on ascorbate concentration. We conclude that nitrogen dioxide radical (NO₂ ^• ), but not ONOO⁻, produced by a guaiacol peroxidase is the intermediate for phytophenolic nitration.

【 授权许可】

Unknown