7-Deoxyloganin 7-hydroxylase in Lonicera japonica cell cultures.
The activity of 7-deoxyloganin 7-hydroxylase, an enzyme catalyzing the conversion of 7-deoxyloganin into loganin, was detected in a microsomal preparation from the cell suspension cultures of Lonicera japonica. It was dependent on NADPH and molecular oxygen. The enzymatic reaction was inhibited by carbon monoxide as well as by several cytochrome P450 inhibitors, especially ketoconazole, indicating that the reaction was mediated by cytochrome P450. The enzyme showed substrate specificity for 7-deoxyloganin. The K(m) values for 7-deoxyloganin and NADPH were estimated as 170 and 18 microM, respectively, from Lineweaver-Burk plots.
Katano
N
N
Department of Pharmacognosy, Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5 chome, Gifu 502-8585, Japan.
Yamamoto
H
H
Iio
R
R
Inoue
K
K
D002248:Carbon Monoxide / Q000494:pharmacology; D002478:Cells, Cultured; D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005960:Glucosides / Q000378:metabolism; D039823:Iridoids; D007654:Ketoconazole / Q000494:pharmacology; D019684:Magnoliopsida / Q000201:enzymology*; D008797:Metyrapone / Q000494:pharmacology; D008825:Miconazole / Q000494:pharmacology; D008861:Microsomes / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D009249:NADP / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D010101:Oxygen Consumption; D011714:Pyrans / Q000378:metabolism
D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors; D005960:Glucosides; D039823:Iridoids; D011714:Pyrans; D009249:NADP; D008825:Miconazole; D002248:Carbon Monoxide; D006899:Mixed Function Oxygenases; C441168:7-Deoxyloganin 7-hydroxylase; C059516:loganin; D007654:Ketoconazole; D010100:Oxygen; D008797:Metyrapone