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ENZYME

ENZYME entry: EC 1.17.99.9

Accepted Name
heme a synthase
Reaction catalysed
2 A + Fe(II)-heme o + H2O = 2 AH2 + Fe(II)-heme a
Comment(s)
  • Contains a heme b cofactor.
  • The enzyme catalyzes the conversion of heme o to heme a by two successive hydroxylations of the methyl group at C-8, using water as the oxygen source.
  • The first hydroxylation forms heme i, the second hydroxylation results in an unstable dihydroxymethyl group, which spontaneously dehydrates, resulting in the formyl group of heme a.
  • The electrons produced by the reaction are transferred to a heme b cofactor.
  • However, the electron acceptor that is used to restore the heme b cofactor to its oxidized state is still not known (both a thioredoxin-like protein and menaquinol have been proposed).
Cross-references
BRENDA1.17.99.9
EC2PDB1.17.99.9
ExplorEnz1.17.99.9
PRIAM enzyme-specific profiles1.17.99.9
KEGG Ligand Database for Enzyme Nomenclature1.17.99.9
IUBMB Enzyme Nomenclature1.17.99.9
IntEnz1.17.99.9
MEDLINEFind literature relating to 1.17.99.9
MetaCyc1.17.99.9
Rhea expert-curated reactions1.17.99.9
UniProtKB/Swiss-Prot
Q9FKT8, COX15_ARATHQ08DG6, COX15_BOVINQ7KZN9, COX15_HUMAN
Q8BJ03, COX15_MOUSEP40086, COX15_YEASTA5FXV3, CTAA1_ACICJ
A5FXV4, CTAA2_ACICJQ7CZN9, CTAA_AGRFCQ04443, CTAA_ALKPO
B9JVB6, CTAA_ALLAMB9KHM9, CTAA_ANAMFQ5PBP7, CTAA_ANAMM
Q2GLK1, CTAA_ANAPZA8I7Y5, CTAA_AZOC5C3P6V3, CTAA_BACAA
C3LI12, CTAA_BACACA0RHW4, CTAA_BACAHQ81MT7, CTAA_BACAN
B7JK34, CTAA_BACC0Q732C1, CTAA_BACC1B7IVI3, CTAA_BACC2
C1EPW0, CTAA_BACC3B7H6T3, CTAA_BACC4B7HMD0, CTAA_BACC7
A7GRX4, CTAA_BACCNB9IW25, CTAA_BACCQQ819N0, CTAA_BACCR
Q635Y0, CTAA_BACCZQ6HEL8, CTAA_BACHKQ65K14, CTAA_BACLD
A9VUA7, CTAA_BACMKA8FCU5, CTAA_BACP2P12946, CTAA_BACSU
A7Z4B0, CTAA_BACVZA1USH8, CTAA_BARBKQ6G3L5, CTAA_BARHE
Q6G011, CTAA_BARQUA9IVC8, CTAA_BART1B2IH44, CTAA_BEII9
Q89KD9, CTAA_BRADUA5EKD5, CTAA_BRASBA4YVQ0, CTAA_BRASO
B2S532, CTAA_BRUA1Q2YNB0, CTAA_BRUA2A6X1W1, CTAA_BRUA4
Q57DW5, CTAA_BRUABA9MAG4, CTAA_BRUC2C0RIC2, CTAA_BRUMB
Q8YGI7, CTAA_BRUMEA5VPX0, CTAA_BRUO2B0CLB4, CTAA_BRUSI
Q8G1D1, CTAA_BRUSUB0T0S6, CTAA_CAUSKQ9A8H9, CTAA_CAUVC
B8H551, CTAA_CAUVNA3PQK0, CTAA_CERS1Q3IXW9, CTAA_CERS4
A4WZ55, CTAA_CERS5B9KW13, CTAA_CERSKQ11J69, CTAA_CHESB
A8LK55, CTAA_DINSHQ3YRB4, CTAA_EHRCJQ2GHG8, CTAA_EHRCR
Q5FG54, CTAA_EHRRGQ5HAH7, CTAA_EHRRWQ2N6M9, CTAA_ERYLH
B1YIW6, CTAA_EXIS2C4L5D6, CTAA_EXISAA5FA69, CTAA_FLAJ1
A6H039, CTAA_FLAPJQ5L115, CTAA_GEOKAP94346, CTAA_GEOTD
A4ILW9, CTAA_GEOTNA9HEV3, CTAA_GLUDAQ0BQ20, CTAA_GRABC
Q9K9M8, CTAA_HALH5Q0BZT0, CTAA_HYPNAQ28PL3, CTAA_JANSC
Q929V9, CTAA_LISINC1KX11, CTAA_LISMCQ71XV6, CTAA_LISMF
B8DH71, CTAA_LISMHQ8Y5K2, CTAA_LISMOA0AKG4, CTAA_LISW6
B1HPV0, CTAA_LYSSCB9EB26, CTAA_MACCJQ0APH6, CTAA_MARMM
B7KV80, CTAA_METC4A9W350, CTAA_METEPB8ISP2, CTAA_METNO
B1ZGD8, CTAA_METPBB1M282, CTAA_METRJB0UR12, CTAA_METS4
Q2GCS4, CTAA_NEOSMQ0AIG6, CTAA_NITECQ82X64, CTAA_NITEU
Q1QKJ7, CTAA_NITHXQ2Y9R4, CTAA_NITMUQ3SSR2, CTAA_NITWN
Q2G350, CTAA_NOVADQ8ER78, CTAA_OCEIHA5CF77, CTAA_ORITB
B3CRU7, CTAA_ORITIA1B8C2, CTAA_PARDPA7HXA1, CTAA_PARL1
Q2W552, CTAA_PARM1Q4FLV1, CTAA_PELUBB3PVH0, CTAA_RHIE6
Q2K9W9, CTAA_RHIECQ1MIP9, CTAA_RHIJ3Q982X5, CTAA_RHILO
B5ZXY9, CTAA_RHILWQ92QR8, CTAA_RHIMEB9JD11, CTAA_RHIR8
A5VF68, CTAA_RHIWRB6IUZ7, CTAA_RHOCSQ2IWP3, CTAA_RHOP2
Q07MP8, CTAA_RHOP5Q6N660, CTAA_RHOPAQ214F0, CTAA_RHOPB
Q136Q9, CTAA_RHOPSB3QKF4, CTAA_RHOPTC3PMV5, CTAA_RICAE
A8GMQ9, CTAA_RICAHA8GXM1, CTAA_RICB8Q1RJX8, CTAA_RICBR
A8EY08, CTAA_RICCKQ92IS7, CTAA_RICCNQ4UKQ2, CTAA_RICFE
A8F119, CTAA_RICM5Q9ZDR8, CTAA_RICPRB0BWT1, CTAA_RICRO
A8GRD0, CTAA_RICRSQ165T0, CTAA_ROSDOQ5LRS1, CTAA_RUEPO
Q1GGZ8, CTAA_RUESTQ8E8P8, CTAA_SHEONQ5WFD1, CTAA_SHOC1
C3MA28, CTAA_SINFNA6U7T3, CTAA_SINMWQ1GWK6, CTAA_SPHAL
A7X127, CTAA_STAA1A6U0T3, CTAA_STAA2Q2FHW5, CTAA_STAA3
Q2G2C0, CTAA_STAA8A5IS02, CTAA_STAA9Q2YX60, CTAA_STAAB
Q5HGW9, CTAA_STAACA6QFX0, CTAA_STAAEQ7A2S8, CTAA_STAAM
Q7A665, CTAA_STAANQ6GHX0, CTAA_STAARQ6GA99, CTAA_STAAS
A8Z1Q0, CTAA_STAATQ7A160, CTAA_STAAWB9DPV8, CTAA_STACT
Q5HQ52, CTAA_STAEQQ8CPM2, CTAA_STAESQ4L5C9, CTAA_STAHJ
Q49WP0, CTAA_STAS1Q67L43, CTAA_SYMTHQ73HV8, CTAA_WOLPM
B3CLF8, CTAA_WOLPPQ5GSI0, CTAA_WOLTRC0R5T8, CTAA_WOLWR
A7ING5, CTAA_XANP2Q10361, ETP1_SCHPO

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All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.17.99.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.17.-.-
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