Obtusifoliol
Obtusifoliol belongs to the class of organic compounds known as ergosterols and derivatives. These are steroids containing ergosta-5,7,22-trien-3beta-ol or a derivative thereof, which is based on the 3beta-hydroxylated ergostane skeleton. Thus, obtusifoliol is considered to be a sterol lipid molecule. Obtusifoliol is found, on average, in the highest concentration within evening primroses. Obtusifoliol has also been detected, but not quantified in, several different foods, such as common chokecherries, jicama, pepper (C. frutescens), avocado, and pecan nuts. This could make obtusifoliol a potential biomarker for the consumption of these foods. Obtusifoliol is an intermediate in the biosynthesis of cholesterol: in a reaction catalyzed by the enzyme CYP51A1 (EC 1.14.13.70, sterol 14-demethylase) (PMID: 9559662). CYP51A1 is a housekeeping enzyme essential for the viability of mammals, an essential step in cholesterol biosynthesis. Sterol 14-demethylation occurs in all organisms exhibiting de novo sterol biosynthesis and CYP51A1 has been conserved throughout evolution (PMID: 8797093).
| ID | EC Number | Name |
|---|---|---|
| KEGG:R03775 | 5.5.1.9 | cycloeucalenol lyase (cyclopropane-decyclizing) |
| KEGG:R05731 | 1.14.14.154 | obtusifoliol,[reduced NADPH---hemoprotein reductase]:oxygen oxidoreductase (14-methyl cleaving) |
| Rhea:RHEA:14918 | 1.14.14.154 | obtusifoliol + 3 reduced [NADPH—hemoprotein reductase] + 3 O2 => 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 3 oxidized [NADPH—hemoprotein reductase] + 4 H2O + 4 H+ |
| Rhea:RHEA:14919 | 1.14.14.154 | 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 3 oxidized [NADPH—hemoprotein reductase] + 4 H2O + 4 H+ => obtusifoliol + 3 reduced [NADPH—hemoprotein reductase] + 3 O2 |
| Rhea:RHEA:14920 | 1.14.14.154 | obtusifoliol + 3 reduced [NADPH—hemoprotein reductase] + 3 O2 <=> 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 3 oxidized [NADPH—hemoprotein reductase] + 4 H2O + 4 H+ |
| Rhea:RHEA:22801 | 5.5.1.9 | cycloeucalenol => obtusifoliol |
| Rhea:RHEA:22802 | 5.5.1.9 | obtusifoliol => cycloeucalenol |
| Rhea:RHEA:22803 | 5.5.1.9 | cycloeucalenol <=> obtusifoliol |
| Rhea:RHEA:56757 | obtusifoliol + 6 reduced [2Fe-2S]-[ferredoxin] + 3 O2 + 5 H+ => 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 6 oxidized [2Fe-2S]-[ferredoxin] + 4 H2O | |
| Rhea:RHEA:56758 | 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 6 oxidized [2Fe-2S]-[ferredoxin] + 4 H2O => obtusifoliol + 6 reduced [2Fe-2S]-[ferredoxin] + 3 O2 + 5 H+ | |
| Rhea:RHEA:56759 | obtusifoliol + 6 reduced [2Fe-2S]-[ferredoxin] + 3 O2 + 5 H+ <=> 4α-methyl-5α-ergosta-8,14,24(28)-trien-3β-ol + formate + 6 oxidized [2Fe-2S]-[ferredoxin] + 4 H2O | |
| BioCyc:1.14.13.70-RXN | 1.14.14.154 | OBTUSIFOLIOL + 3 OXYGEN-MOLECULE + 3 Red-NADPH-Hemoprotein-Reductases --> ALPHA-METHYL-5-ALPHA-ERGOSTA + FORMATE + 4 WATER + 3 Ox-NADPH-Hemoprotein-Reductases + PROTON |
| BioCyc:CYCLOEUCALENOL-CYCLOISOMERASE-RXN | 5.5.1.9 | CYCLOEUCALENOL --> OBTUSIFOLIOL |
| BioCyc:RXN-19831 | OBTUSIFOLIOL + OXYGEN-MOLECULE + Red-NADPH-Hemoprotein-Reductases --> CPD-21438 + WATER + Ox-NADPH-Hemoprotein-Reductases | |
| BioCyc:RXN-13896 | 2.1.1.- | S-ADENOSYLMETHIONINE + OBTUSIFOLIOL --> CPD-14905 + ADENOSYL-HOMO-CYS + PROTON |
| Rhea:RHEA:14917 | [14917] obtusifoliol + 3 reduced [NADPH--hemoprotein reductase] + 3 O2 = 4alpha-methyl-5alpha-ergosta-8,14,24(28)-trien-3beta-ol + formate + 3 oxidized [NADPH--hemoprotein reductase] + 4 H2O + 4 H(+) | |
| Rhea:RHEA:22800 | [22800] cycloeucalenol = obtusifoliol | |
| Rhea:RHEA:56756 | [56756] obtusifoliol + 6 reduced [2Fe-2S]-[ferredoxin] + 3 O2 + 5 H(+) = 4alpha-methyl-5alpha-ergosta-8,14,24(28)-trien-3beta-ol + formate + 6 oxidized [2Fe-2S]-[ferredoxin] + 4 H2O |