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Your query returned 3 entries. 
Printable version
| EC | 1.3.99.27 | ||||||
| Accepted name: | 1-hydroxycarotenoid 3,4-desaturase | ||||||
| Reaction: | 1-hydroxy-1,2-dihydrolycopene + acceptor = 1-hydroxy-3,4-didehydro-1,2-dihydrolycopene + reduced acceptor | ||||||
| Other name(s): | CrtD; hydroxyneurosporene desaturase; carotenoid 3,4-dehydrogenase; 1-hydroxy-carotenoid 3,4-dehydrogenase | ||||||
| Systematic name: | 1-hydroxy-1,2-dihydrolycopene:acceptor oxidoreductase | ||||||
| Comments: | The enzymes from Rubrivivax gelatinosus and Rhodobacter sphaeroides prefer the acyclic carotenoids (e.g. 1-hydroxy-1,2-dihydroneurosporene, 1-hydroxy-1,2-dihydrolycopene) as substrates. The conversion rate for the 3,4-desaturation of the monocyclic 1′-hydroxy-1′,2′-dihydro-γ-carotene is lower [2,3]. The enzyme from the marine bacterium strain P99-3 shows high activity with the monocyclic carotenoid 1′-hydroxy-1′,2′-dihydro-γ-carotene [1]. The enzyme from Rhodobacter sphaeroides utilizes molecular oxygen as the electron acceptor in vitro [3]. However, oxygen is unlikely to be the natural electron acceptor under anaerobic conditions. | ||||||
| Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc, PDB | ||||||
| References: |
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| EC | 1.14.15.9 | ||||||
| Accepted name: | spheroidene monooxygenase | ||||||
| Reaction: | (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) (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) (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) (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) |
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| For diagram of 2,2′-dioxospirilloxanthin biosynthesis, click here and for diagram of 4.2.1.131, click here | |||||||
| Glossary: | spheroidene = 3,4-didehydro-1-methoxy-1,2,7′,8′-tetrahydro-ψ,ψ-carotene | ||||||
| Other name(s): | CrtA; acyclic carotenoid 2-ketolase; spirilloxanthin monooxygenase; 2-oxo-spirilloxanthin monooxygenase | ||||||
| Systematic name: | spheroidene,reduced-ferredoxin:oxygen oxidoreductase (spheroiden-2-one-forming) | ||||||
| Comments: | 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]. | ||||||
| Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||
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| EC | 2.1.1.210 | ||||||
| Accepted name: | demethylspheroidene O-methyltransferase | ||||||
| Reaction: | S-adenosyl-L-methionine + demethylspheroidene = S-adenosyl-L-homocysteine + spheroidene | ||||||
| For diagram of 4.2.1.131, click here and for diagram of mechanism, click here | |||||||
| Other name(s): | 1-hydroxycarotenoid O-methylase; 1-hydroxycarotenoid methylase; 1-HO-carotenoid methylase; CrtF | ||||||
| Systematic name: | S-adenosyl-L-methionine:demethylspheroidene O-methyltransferase | ||||||
| Comments: | In Rhodopseudomonas capsulata and Rubrivivax gelatinosus the enzyme is involved in biosynthesis of spheroidene [1,2,3]. In Rubrivivax gelatinosus the enzyme also catalyses the methylation of demethylspirilloxanthin to spirilloxanthin and the methylation of 3,4-didehydrorhodopin to anhydrorhodovibrin [2]. | ||||||
| Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||
| References: |
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