Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen into the other donor
BRITE hierarchy

spheroidene,reduced-ferredoxin:oxygen oxidoreductase (spheroiden-2-one-forming)

(1) spheroidene + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = spheroiden-2-one + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction) [RN:R07537];
(1a) spheroidene + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2-hydroxyspheroidene + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O;
(1b) 2-hydroxyspheroidene + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2,2-dihydroxyspheroidene + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O;
(1c) 2,2-dihydroxyspheroidene = spheroiden-2-one + H2O (spontaneous);
(2) spirilloxanthin + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = 2-oxospirilloxanthin + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction) [RN:R07525];
(2a) spirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2-hydroxyspirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O;
(2b) 2-hydroxyspirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2,2-dihydroxyspirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O;
(2c) 2,2-dihydroxyspirilloxanthin = 2-oxospirilloxanthin + H2O (spontaneous);
(3) 2-oxospirilloxanthin + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = 2,2'-dioxospirilloxanthin + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction) [RN:R07526];
(3a) 2-oxospirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2'-hydroxy-2-oxospirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O;
(3b) 2'-hydroxy-2-oxospirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2',2'-dihydroxy-2-oxospirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O;
(3c) 2',2'-dihydroxy-2-oxospirilloxanthin = 2,2'-dioxospirilloxanthin + H2O (spontaneous)

R07525 R07526 R07537;
(other) R07538
Reaction

spheroidene [CPD:C15900];
reduced ferredoxin [iron-sulfur] cluster [CPD:C00138];
O2 [CPD:C00007];
H+ [CPD:C00080];
2-hydroxyspheroidene;
2,2-dihydroxyspheroidene;
spirilloxanthin [CPD:C15881];
2-hydroxyspirilloxanthin;
2,2-dihydroxyspirilloxanthin;
2-oxospirilloxanthin [CPD:C15884];
2'-hydroxy-2-oxospirilloxanthin;
2',2'-dihydroxy-2-oxospirilloxanthin

The enzyme is involved in spheroidenone biosynthesis and in 2,2'-dioxospirilloxanthin biosynthesis. The enzyme from Rhodobacter sphaeroides contains heme at its active site [1].

EC 1.14.15.9 created 2012, modified 2016

1  [PMID:20851979]

2  [PMID:19136077]