Formation of benzoquinol moiety in cornoside by salidroside mono-oxygenase, a cytochrome P450 enzyme, from Abeliophyllum distichum cell suspension cultures
| Autor: | Hirobumi Yamamoto, Kenichiro Inoue, Mitsuko Hori, Hiroshi Kuwajima |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Oxygenase
Miconazole Stereochemistry Oleaceae Cytochrome c Group Plant Science Mixed Function Oxygenases chemistry.chemical_compound Cytochrome P-450 Enzyme System Glucosides Phenols Glucoside Benzoquinones Genetics Cytochrome P-450 Enzyme Inhibitors Cells Cultured chemistry.chemical_classification Carbon Monoxide biology Cyclohexanones Chemistry Cytochrome c Salidroside Cytochrome P450 Hydrogen-Ion Concentration biology.organism_classification Abeliophyllum Oxygen Enzyme biology.protein Microsome Reactive Oxygen Species NADP |
| Zdroj: | Planta. 216:432-436 |
| ISSN: | 1432-2048 0032-0935 |
| DOI: | 10.1007/s00425-002-0896-0 |
| Popis: | A microsomal fraction prepared from Abeliophyllum distichumNakai (Oleaceae) cell suspension cultures oxidized salidroside, a glucoside of 4-hydroxyphenylethyl alcohol, to cornoside possessing a unique benzoquinol ring. The enzyme named salidroside mono-oxygenase required NADPH as the only cofactor, and molecular oxygen. The reaction was strongly inhibited by CO as well as several cytochrome P450 inhibitors, such as cytochrome c and miconazole, indicating the involvement of a cytochrome P450 enzyme. Salidroside mono-oxygenase accepted salidroside as the only substrate, but did not oxidize 4-hydroxyphenylethyl alcohol, the salidroside aglucone, and 4-hydroxybenzoic acid. The optimum pH of the reaction was 7.5, and apparent K(m) values for salidroside and NADPH were 44 micro M and 33 micro M, respectively. The benzoquinol ring formation mechanism is discussed in comparison to the mechanism for ipso substitution of 4-hydroxybenzoate by active oxygen species followed by elimination leading to hydroquinone. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink