AC MF_03193; DC Protein; auto TR HAMAP; MF_03193; -; 1; level=0 XX Names: COQ6_monooxygenase XX ID COQ6 DE RecName: Full=Ubiquinone biosynthesis monooxygenase COQ6, mitochondrial; DE EC=1.14.15.45; DE AltName: Full=2-methoxy-6-polyprenolphenol 4-hydroxylase; DE EC=1.14.15.46; case DE + AltName: Full=Coenzyme Q10 monooxygenase 6; end case case DE + AltName: Full=Ubiquinone C4-deaminase; DE EC=3.5.-.-; end case case or or GN Name=COQ6; else case GN Name=Coq6; else case or GN Name=coq6; else case GN Name=coq-6; end case XX case CC -!- FUNCTION: FAD-dependent monooxygenase required for two non-consecutive CC steps during ubiquinone biosynthesis. Required for the C5-ring CC hydroxylation during ubiquinone biosynthesis by catalyzing the CC hydroxylation of 4-hydroxy-3-(all-trans-decaprenyl)benzoic acid to 3,4- CC dihydroxy-5-(all-trans-decaprenyl)benzoic acid. Also acts downstream of CC COQ4, for the C1-hydroxylation during ubiquinone biosynthesis by CC catalyzing the hydroxylation of 2-methoxy-6-(all-trans- CC decaprenyl)phenol to 2-methoxy-6-(all-trans-decaprenyl)benzene-1,4- CC diol. The electrons required for the hydroxylation reaction are CC funneled indirectly to COQ6 from NADPH via a ferredoxin/ferredoxin CC reductase system composed of FDX2 and FDXR. CC -!- CATALYTIC ACTIVITY: CC Reaction=4-hydroxy-3-(all-trans-decaprenyl)benzoate + 2 reduced [2Fe- CC 2S]-[ferredoxin] + O2 + 2 H(+) = 3,4-dihydroxy-5-(all-trans- CC decaprenyl)benzoate + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81259, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:62793, CC ChEBI:CHEBI:84503; EC=1.14.15.45; CC -!- CATALYTIC ACTIVITY: CC Reaction=2-methoxy-6-(all-trans-decaprenyl)phenol + 2 reduced [2Fe-2S]- CC [ferredoxin] + O2 + 2 H(+) = 2-methoxy-6-(all-trans- CC decaprenyl)benzene-1,4-diol + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81295, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:50774, CC ChEBI:CHEBI:64180; EC=1.14.15.46; else case CC -!- FUNCTION: FAD-dependent monooxygenase required for two non-consecutive CC steps during ubiquinone biosynthesis. Required for the C5-ring CC hydroxylation during ubiquinone biosynthesis by catalyzing the CC hydroxylation of 4-hydroxy-3-(all-trans-hexaprenyl)benzoic acid to 3,4- CC dihydroxy-5-(all-trans-hexaprenyl)benzoic acid. Also acts downstream of CC COQ4, for the C1-hydroxylation during ubiquinone biosynthesis by CC catalyzing the hydroxylation of 2-methoxy-6-(all-trans- CC hexaprenyl)phenol to 2-methoxy-6-(all-trans-hexaprenyl)benzene-1,4- CC diol. The electrons required for the hydroxylation reaction are CC funneled indirectly from NADPH via ferredoxin (YAH1) and ferredoxin CC reductase (ARH1) to COQ6. Can also convert 3-hexaprenyl-4-aminobenzoic CC acid (HAB), a COQ2-prenylated pABA, to DHHB in a two step process. HAB CC is first hydroxylated at C5 to yield 3-hexaprenyl-4-amino-5- CC hydroxybenzoic acid (HHAB) which is further deaminated at C4 by COQ6 to CC produce DHHB. CC -!- CATALYTIC ACTIVITY: CC Reaction=4-hydroxy-3-(all-trans-hexaprenyl)benzoate + 2 reduced [2Fe- CC 2S]-[ferredoxin] + O2 + 2 H(+) = 3,4-dihydroxy-5-(all-trans- CC hexaprenyl)benzoate + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:20361, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:58373, CC ChEBI:CHEBI:84492; EC=1.14.15.45; CC -!- CATALYTIC ACTIVITY: CC Reaction=2-methoxy-6-(all-trans-hexaprenyl)phenol + 2 reduced [2Fe-2S]- CC [ferredoxin] + O2 + 2 H(+) = 2-methoxy-6-(all-trans- CC hexaprenyl)benzene-1,4-diol + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81279, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:1109, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, CC ChEBI:CHEBI:15379, ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, CC ChEBI:CHEBI:61472; EC=1.14.15.46; CC -!- CATALYTIC ACTIVITY: CC Reaction=4-amino-3-(all-trans-hexaprenyl)benzoate + 2 reduced [2Fe-2S]- CC [ferredoxin] + O2 + 2 H(+) = 4-amino-5-hydroxy-3-(all-trans- CC hexaprenyl)benzoate + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:58392, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:142618, CC ChEBI:CHEBI:142619; CC -!- CATALYTIC ACTIVITY: CC Reaction=4-amino-5-hydroxy-3-(all-trans-hexaprenyl)benzoate + 4 reduced CC [2Fe-2S]-[ferredoxin] + O2 + 5 H(+) = 3,4-dihydroxy-5-(all-trans- CC hexaprenyl)benzoate + 4 oxidized [2Fe-2S]-[ferredoxin] + NH4(+) + CC H2O; Xref=Rhea:RHEA:58396, Rhea:RHEA-COMP:10000, Rhea:RHEA- CC COMP:10001, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:28938, ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, CC ChEBI:CHEBI:58373, ChEBI:CHEBI:142619; else case CC -!- FUNCTION: FAD-dependent monooxygenase required for two non-consecutive CC steps during ubiquinone biosynthesis. Required for the C5-ring CC hydroxylation during ubiquinone biosynthesis by catalyzing the CC hydroxylation of 4-hydroxy-3-(all-trans-decaprenyl)benzoic acid to 3,4- CC dihydroxy-5-(all-trans-decaprenyl)benzoic acid. Also acts downstream of CC COQ4, for the C1-hydroxylation during ubiquinone biosynthesis by CC catalyzing the hydroxylation of 2-methoxy-6-(all-trans- CC decaprenyl)phenol to 2-methoxy-6-(all-trans-decaprenyl)benzene-1,4- CC diol. The electrons required for the hydroxylation reaction are CC funneled indirectly to coq6 from NADPH via a ferredoxin/ferredoxin CC reductase system. CC -!- CATALYTIC ACTIVITY: CC Reaction=4-hydroxy-3-(all-trans-decaprenyl)benzoate + 2 reduced [2Fe- CC 2S]-[ferredoxin] + O2 + 2 H(+) = 3,4-dihydroxy-5-(all-trans- CC decaprenyl)benzoate + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81259, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:62793, CC ChEBI:CHEBI:84503; EC=1.14.15.45; CC -!- CATALYTIC ACTIVITY: CC Reaction=2-methoxy-6-(all-trans-decaprenyl)phenol + 2 reduced [2Fe-2S]- CC [ferredoxin] + O2 + 2 H(+) = 2-methoxy-6-(all-trans- CC decaprenyl)benzene-1,4-diol + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81295, Rhea:RHEA-COMP:10000, Rhea:RHEA-COMP:10001, CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:50774, CC ChEBI:CHEBI:64180; EC=1.14.15.46; else CC -!- FUNCTION: FAD-dependent monooxygenase required for two non-consecutive CC steps during ubiquinone biosynthesis. Required for the C5-ring CC hydroxylation during ubiquinone biosynthesis by catalyzing the CC hydroxylation of 4-hydroxy-3-(all-trans-polyprenyl)benzoic acid to 3,4- CC dihydroxy-5-(all-trans-polyprenyl)benzoic acid. Also acts downstream of CC coq4, for the C1-hydroxylation during ubiquinone biosynthesis by CC catalyzing the hydroxylation of 2-methoxy-6-(all-trans- CC polyprenyl)phenol to 2-methoxy-6-(all-trans-polyprenyl)benzene-1,4- CC diol. The electrons required for the hydroxylation reaction are CC funneled indirectly to coq6 from NADPH via a ferredoxin/ferredoxin CC reductase system. CC -!- CATALYTIC ACTIVITY: CC Reaction=a 4-hydroxy-3-(all-trans-polyprenyl)benzoate + 2 reduced [2Fe- CC 2S]-[ferredoxin] + O2 + 2 H(+) = a 3,4-dihydroxy-5-(all-trans- CC polyprenyl)benzoate + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81195, Rhea:RHEA-COMP:9514, Rhea:RHEA-COMP:10000, CC Rhea:RHEA-COMP:10001, Rhea:RHEA-COMP:10930, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:33737, CC ChEBI:CHEBI:33738, ChEBI:CHEBI:64694, ChEBI:CHEBI:78396; CC EC=1.14.15.45; CC -!- CATALYTIC ACTIVITY: CC Reaction=a 2-methoxy-6-(all-trans-polyprenyl)phenol + 2 reduced [2Fe- CC 2S]-[ferredoxin] + O2 + 2 H(+) = a 2-methoxy-6-(all-trans- CC polyprenyl)benzene-1,4-diol + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O; CC Xref=Rhea:RHEA:81183, Rhea:RHEA-COMP:9551, Rhea:RHEA-COMP:10000, CC Rhea:RHEA-COMP:10001, Rhea:RHEA-COMP:10858, ChEBI:CHEBI:15377, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:33737, CC ChEBI:CHEBI:33738, ChEBI:CHEBI:62731, ChEBI:CHEBI:84166; CC EC=1.14.15.46; end case CC -!- COFACTOR: CC Name=FAD; Xref=ChEBI:CHEBI:57692; CC -!- PATHWAY: Cofactor biosynthesis; ubiquinone biosynthesis. case CC -!- SUBUNIT: Component of a multi-subunit COQ enzyme complex, composed of CC at least @gn(COQ3), @gn(COQ4), @gn(COQ5), @gn(COQ6), @gn(COQ7) and CC @gn(COQ9). Interacts with @gn(COQ8B) and @gn(COQ7). else case CC -!- SUBUNIT: Component of a multi-subunit COQ enzyme complex, composed of CC at least @gn(COQ3), @gn(COQ4), @gn(COQ5), @gn(COQ6), @gn(COQ7) and CC @gn(COQ9). else CC -!- SUBUNIT: Component of a multi-subunit COQ enzyme complex. end case case CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane; Peripheral membrane CC protein; Matrix side. Golgi apparatus. Cell projection. Note=Localizes CC to cell processes and Golgi apparatus in podocytes. else CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane; Peripheral membrane CC protein; Matrix side. end case case not CC -!- MISCELLANEOUS: This protein may be expected to contain an N-terminal CC transit peptide but none has been predicted. end case CC -!- SIMILARITY: Belongs to the UbiH/COQ6 family. XX DR PROSITE; PS01304; UBIH; 1; trigger=no DR Pfam; PF01494; FAD_binding_3; 1; trigger=no DR PRINTS; PR00420; RNGMNOXGNASE; 1; trigger=no DR NCBIfam; TIGR01989; COQ6; 1; trigger=no DR NCBIfam; TIGR01988; Ubi-OHases; 1; trigger=no DR General; TransitM; -; 0-1; trigger=yes XX KW FAD KW Flavoprotein KW Membrane KW Mitochondrion KW Mitochondrion inner membrane KW Monooxygenase KW Oxidoreductase KW Ubiquinone biosynthesis case KW Cell projection KW Golgi apparatus end case XX GO GO:0031314; C:extrinsic component of mitochondrial inner membrane case GO GO:0042995; C:cell projection GO GO:0005794; C:Golgi apparatus end case GO GO:0016712; F:oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen GO GO:0006744; P:ubiquinone biosynthetic process XX FT None XX Size: 451-605; Related: None; Template: P53318; Q9Y2Z9; Scope: Eukaryota Fusion: Nter: None Cter: None Duplicate: None Plasmid: None Comments: None XX # Version: 13 # Last updated date: 2025-04-01 # Created date: 2015-03-20 //