A novel hydroxylase from Catharanthus roseus participating in the hydroxylation of 2-hydroxybenzoic acid.
A novel 55-kDa hydroxylase was isolated from cultured cells of Catharanthus roseus by a three-step procedure: anion exchange chromatography, affinity chromatography and hydroxylapatite adsorption chromatography. The enzyme specifically catalyzed the hydroxylation of 2-hydroxybenzoic acid to give 2,5-dihydroxybenzoic acid. The enzyme activity was optimal at pH 7.8 and was completely inhibited by divalent cations, such as Cu(2+) and Hg(2+). The enzyme showed sequence similarity to certain plant flavonoid 3'-hydroxylases.
Shimoda
Kei
K
Department of Pharmacology and Therapeutics, Faculty of Medicine, Oita University, 1-1 Hasama-machi, Oita 879-5593, Japan. shimoda@med.oita-u.ac.jp
Kubota
Naoji
N
Sano
Takayuki
T
Hirakawa
Hidetada
H
Hirata
Toshifumi
T