KEGG   ENZYME: 1.14.15.9Help
Entry
EC 1.14.15.9                Enzyme                                 

Name
spheroidene monooxygenase;
CrtA;
acyclic carotenoid 2-ketolase;
spirilloxanthin monooxygenase;
2-oxo-spirilloxanthin monooxygenase
Class
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
Sysname
spheroidene,reduced-ferredoxin:oxygen oxidoreductase (spheroiden-2-one-forming)
Reaction(IUBMB)
(1) spheroidene + 2 reduced ferredoxin [iron-sulfur] cluster + 2 O2 = spheroiden-2-one + 2 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction) [RN:R07537];
(1a) spheroidene + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2-hydroxyspheroidene + oxidized ferredoxin [iron-sulfur] cluster + H2O [RN:R07525];
(1b) 2-hydroxyspheroidene + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2,2-dihydroxyspheroidene + oxidized ferredoxin [iron-sulfur] cluster + H2O [RN:R07526];
(1c) 2,2-dihydroxyspheroidene = spheroiden-2-one + H2O (spontaneous);
(2) spirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + 2 O2 = 2-oxospirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction);
(2a) spirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2-hydroxyspirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O;
(2b) 2-hydroxyspirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2,2-dihydroxyspirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O;
(2c) 2,2-dihydroxyspirilloxanthin = 2-oxospirilloxanthin + H2O (spontaneous);
(3) 2-oxospirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + 2 O2 = 2,2'-dioxospirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction);
(3a) 2-oxospirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2'-hydroxy-2-oxospirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O;
(3b) 2'-hydroxy-2-oxospirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2H+ = 2',2'-dihydroxy-2-oxospirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O;
(3c) 2',2'-dihydroxy-2-oxospirilloxanthin = 2,2'-dioxospirilloxanthin + H2O (spontaneous)
Reaction(KEGG)
Substrate
spheroidene [CPD:C15900];
reduced ferredoxin [iron-sulfur] cluster [CPD:C00138];
O2 [CPD:C00007];
2H+;
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
Product
spheroiden-2-one [CPD:C15903];
oxidized ferredoxin [iron-sulfur] cluster [CPD:C00139];
H2O [CPD:C00001];
2-hydroxyspheroidene;
2,2-dihydroxyspheroidene;
2-oxospirilloxanthin [CPD:C15884];
2-hydroxyspirilloxanthin;
2,2-dihydroxyspirilloxanthin;
2,2'-dioxospirilloxanthin [CPD:C15885];
2'-hydroxy-2-oxospirilloxanthin;
2',2'-dihydroxy-2-oxospirilloxanthin
Comment
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].
History
EC 1.14.15.9 created 2012, modified 2016
Pathway
Carotenoid biosynthesis
Metabolic pathways
Orthology
K09847  
spheroidene monooxygenase
Genes
RSP: 
RSP_0272(crtA)
RSH: 
RSQ: 
RSK: 
RCP: 
JAN: 
Jann_0144(crtA)
RDE: 
RD1_0121(crtA)
RLI: 
DSH: 
Dshi_3501(crtA)
Taxonomy
Reference
1  [PMID:20851979]
  Authors
Lee PC, Holtzapple E, Schmidt-Dannert C
  Title
Novel activity of Rhodobacter sphaeroides spheroidene monooxygenase CrtA expressed in Escherichia coli.
  Journal
Appl. Environ. Microbiol. 76 (2010) 7328-31.
  Sequence
Reference
2  [PMID:19136077]
  Authors
Gerjets T, Steiger S, Sandmann G
  Title
Catalytic properties of the expressed acyclic carotenoid 2-ketolases from Rhodobacter capsulatus and Rubrivivax gelatinosus.
  Journal
Biochim. Biophys. Acta. 1791 (2009) 125-31.
  Sequence
Other DBs
ExplorEnz - The Enzyme Database: 
IUBMB Enzyme Nomenclature: 
ExPASy - ENZYME nomenclature database: 
BRENDA, the Enzyme Database: 

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