Table 1.
Human flavoproteins.
| No. | E.C. | Enzyme | Cofactor | Structure clan (family)⁎ | Gene symbol | Gene location |
|---|---|---|---|---|---|---|
| 1 | 1.1.1.28 | d-lactate dehydrogenase | FAD | FAD_PCMH (FAD_binding_4) | LDHD | 16q23.1 |
| 2 | 1.1.1.204 | Xanthine dehydrogenase | FAD | FAD_PCMH (FAD_binding_5) | XDH | 2p23.1 |
| 3 | 1.1.3.15 | (S)-2-hydroxy-acid oxidase | FMN | TIM_barrel (FMN_dh) | HAO1 | 20p12.3 |
| HAO2 | 1p12 | |||||
| 4 | 1.1.5.3 | Glycerol 3-phosphate dehydrogenase | FAD | NADP_Rossmann (DAO) | GPD2 | 2q24.1 |
| 5 | 1.1.99.1 | Choline dehydrogenase | FAD | GMC_ oxred | CHDH | 3p21.1 |
| 6 | 1.1.99.2 | l-2-Hydroxyglutarate dehydrogenase | FAD | -------------------------------------- | L2HGDH | 14q21.3 |
| 7 | 1.1.99.- | d-2-Hydroxyglutarate dehydrogenase | FAD | -------------------------------------- | D2HGDH | 2q37.3 |
| 8 | 1.2.3.1 | Aldehyde oxidase | FAD | -------------------------------------- | AOX1 | 2q33.1 |
| 9 | 1.3.1.2 | Dihydropyrimidine dehydrogenase | FMN | TIM_barrel (DHO_dh) | DPYD | 1p21.3 |
| FAD | NADP_Rossmann (Pyr_redox_2) | |||||
| 10 | 1.3.1.72 | 3β-Hydroxysterol Δ24-reductase | FAD | -------------------------------------- | DHCR24 | 1p32.3 |
| 11 | 1.3.3.1 | Dihydroorotate dehydrogenase | FMN | TIM_barrel (DHO_dh) | DHODH | 16q22.2 |
| 12 | 1.3.3.4 | Protoporphyrinogen IX oxidase | FAD | NADP_Rossmann (Amino_oxidase) | PPOX | 1q23.3 |
| 13 | 1.3.3.6 | Acyl-CoA oxidase | FAD | Acyl-CoA_dh | ACOX1 | 17q25.1 |
| (ACOX, acyl-CoA_dh_1) | ACOX2 | 3p14.3 | ||||
| ACOX3 | 4p16.1 | |||||
| 14 | 1.3.3.- | Glutaryl-CoA oxidase | FAD | -------------------------------------- | C7orf10 | 7p14.1 |
| 15 | 1.3.5.1 | Succinate dehydrogenase | 8α-(N3-His)- | NAPH_Rossmann (FAD_binding_2) | SDHA | 5p15.33 |
| Flavoprotein subunit A | -FAD | (3q29)a | ||||
| 16 | 1.3.99.2 | Short-chain- (butyryl-) acyl CoA dehydrogenase | FAD | Acyl-CoA_dh (Acyl_CoA_dh_1) | ACADS | 12q24.31 |
| 17 | 1.3.99.3 | Medium-chain acyl-CoA dehydrogenase | FAD | Acyl-CoA_dh (Acyl_CoA_dh_1) | ACADM | 1p31.1 |
| 18 | 1.3.99.7 | Glutaryl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | GCDH | 19p13.2 |
| 19 | 1.3.99.10 | Isovaleryl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | IVD | 15q15.1 |
| 20 | 1.3.99.12 | 2-Methylbutyryl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACADSB | 10q26.13 |
| 21 | 1.3.99.13 | Long-chain-acyl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACADL | 2q34 |
| 22 | 1.3.99.- | Very long-chain acyl-CoA dh | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACADVL | 17p13.1 |
| 23 | 1.3.99.- | Isobutyryl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACAD8 | 11q25 |
| 24 | 1.3.99.- | Long-chain-unsaturated-acyl-CoA dh (molecular chaperone of complex I) | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACAD9 | 3q21.3 |
| 25 | 1.3.99.- | Long- and branched-chain-acyl-CoA dh | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACAD10 | 12q24.1 |
| 26 | 1.3.99.- | C22-long-chain-acyl-CoA dehydrogenase | FAD | Acyl-CoA_dh (acyl-CoA_dh_1) | ACAD11 | 3q22.1 |
| 27 | 1.4.3.1 | d-aspartate oxidase | FAD | NADP_Rossmann (DAO) | DDO | 6q21 |
| 28 | 1.4.3.2 | l-amino acid oxidase | FAD | NADP_Rossmann (Amino_oxidase) | LAO | 19q13.3-q13.4 |
| 29 | 1.4.3.3 | d-amino acid oxidase | FAD | NADP_Rossmann (DAO) | DAO | 12q24.11 |
| 30 | 1.4.3.4 | Monoamine oxidase | 8α-(Cys)-FAD | NADP_Rossmann (Amino_oxidase) | MAOA | Xp11.3 |
| MAOB | Xp11.3b | |||||
| 31 | 1.4.3.5 | Pyridoxal 5’-phosphate oxidase | FMN | FMN-binding (Pyridox_oxidase) | PNPO | 17q21.32 |
| Pyridoxine 5’-phosphate oxidase | ||||||
| 32 | 1.4.3.- | Catecholamine oxidase (renalase) | FAD | NADP_Rossmann (Amino_oxidase) | RNLS | 10q23.31 |
| 33 | 1.5.1.20 | Methylenetetrahydrofolate reductase | FAD | FAD_oxidored (MTHFR) | MTHFR | 1p36.22 |
| 34 | 1.5.3.7 | l-pipecolate oxidase | 8α-(Cys)-FAD | NADP_Rossmann (DAO) | PIPOX | 17q11.2 |
| 35 | 1.5.3.16 | Spermine oxidase | FAD | NADP_Rossmann (Amino_oxidase) | SMO | 20p13 |
| 36 | 1.5.5.1 | Electron-transferring flavoprotein-ubiquinone oxidoreductase | FAD | 4Fe-4S (ETF_QO) | ETFDH | 4q32.1 |
| 37 | -------- | Electron transferring flavoprotein | FAD | FAD_DHS (ETF_alpha) | ETFA | 15q24.2-q24.3 |
| HUB (ETF) | ETFB | 19q13.41 | ||||
| 38 | 1.5.99.1 | Sarcosine dehydrogenase | 8α-(N3-His)- | NADP_Rossmann (DAO) | SARDH | 9q34.2 |
| -FAD | ||||||
| 39 | 1.5.99.2 | Dimethylglycine dehydrogenase | 8α-(N3-His) | NADP_Rossmann (DAO) | DMGDH | 5q14.1 |
| -FAD | ||||||
| 40 | 1.5.99.- | Lysine-specific histone demethylase | FAD | NADP_Rossmann | KDM1A | 1p36.12 |
| 41 | 1.5.99.8 | Proline dehydrogenase | FAD | FAD_oxidored (Pro_dh) | PRODH | 22q11.21 |
| 42 | 1.6.2.2 | Cytochrome-b5 reductase | FAD | FAD_Lum_binding (FAD_binding_6) | CYB5R3 | 22q13.2 |
| 43 | 1.6.2.4 | NADPH-hemoprotein reductase | FMN | Flavoprotein (flavodoxin_1) | POR | 7q11.23 |
| (cytochrome P450 reductase) | FAD | FAD_Lum_binding (FAD_binding_1) | ||||
| 44 | 1.6.5.2 | NAD(P)H dehydrogenase (quinone) | FAD | Flavoprotein (Flavodoxin_2) | NQO1 | 16q22.1 |
| 45 | 1.6.5.3 | NADH-ubiquinone oxidoreductase of complex I, subunit UQOR1 | FMN | complex1_51K | NDUFV1 | 11q13.2 |
| 46 | 1.6.-.- | NADPH-dep. diflavin oxidoreductase 1 | FMN | Flavoprotein (Flavodoxin_1) | NDOR1 | 9q34.3 |
| FAD | FAD_Lum_binding (FAD_binding_1) | |||||
| 47 | 1.6.-.- | tRNA dihydrouridine synthase | FMN | TIM_barrel (Dus) | DUS2L | 16q22.1 |
| 48 | 1.8.1.4 | Dihydrolipoyl dehydrogenase | FAD | NADP_Rossmann (Pyr_redox_2) | DLD | 7q31.1 |
| 49 | 1.8.1.7 | Glutathione-disulfide reductase | FAD | NADP_Rossmann (Pyr_redox_2) | GSR | 8p12 |
| 50 | 1.8.1.9 | Thioredoxin-disulfide reductase | FAD | NADP_Rossmann (Pyr_redox_2) | TXNR1 | 12q23.3 |
| TXNR2 | 22q11.21 | |||||
| TXNR3 | 3q21.3 | |||||
| 51 | 1.8.1.- | ER flavoprotein associated with degr. | FAD | -------------------------------------- | FOXRED2 | 22q12.3 |
| 52 | 1.8.3.2 | Sulfhydryl oxidase | FAD | Erv1_Alr | GFER | 16p13.3 |
| 53 | 1.8.3.5 | Prenylcysteine oxidase | FAD | -------------------------------------- | PCYOX1 | 2p13.3 |
| 54 | 1.10.99.2 | Ribosyldihydronicotinamide | FAD | Flavoprotein (Flavodoxin_2) | NQO2 | 6p25.2 |
| dehydrogenase | ||||||
| 55 | 1.14.13.8 | Flavin-containing monooxygenases | FAD | -------------------------------------- | FMO1 | 1q24.3 |
| FMO2 | 1q24.3 | |||||
| FMO3 | 1q24.3 | |||||
| FMO4 | 1q24.3 | |||||
| FMO5 | 1q21.1 | |||||
| 56 | 1.14.13.9 | Kynurenine 3-monooxygenase | FAD | -------------------------------------- | KMO | 1q43 |
| 57 | 1.14.13.39 | Nitric-oxide synthase | FMN | Flavoprotein (Flavodoxin_1) | NOS1 | 12q24.22 |
| FAD | FAD_Lum_binding (FAD_binding_1) | NOS2 | 17q11.2 | |||
| NOS3 | 7q36.1 | |||||
| 58 | 1.14.13.132 | Squalene monooxygenase | FAD | -------------------------------------- | SQLE | 8q24.13 |
| 59 | 1.14.99.- | Monooxygenase in coenzyme Q biosyn. | FAD? | -------------------------------------- | COQ6 | 14q24.3 |
| 60 | 1.16.1.2 | Ferrireductase (biliverdin IX beta red.) | FMN? | N-terminal domain (1-215) | STEAP3 | 2q14.2 |
| 61 | 1.16.1.8 | Methionine synthase reductase | FMN | Flavoprotein (Flavodoxin_1) | MTRR | 5p15.31 |
| FAD | FAD_Lum_binding (FAD_binding_1) | |||||
| 62 | 1.18.1.2 | Ferredoxin-NADP+ reductase | FAD | FAD_Lum_binding (FAD_binding_6) | FDXR | 17q25.1 |
| 63 | 1.-.-.- | NAD(P)H oxidase cytochrome b(558), beta subunit | FAD | -------------------------------------- | CYBB | Xp11.4 |
| 64 | 1.-.-.- | Thyroid oxidase / dual oxidase | FAD | -------------------------------------- | DUOX1 | 15q21.1 |
| DUOX2 | 15q21.1 | |||||
| 65 | 2.2.1.6 | Acetolactate synthase-like protein | FAD? | -------------------------------------- | - | 19p13.12 |
| 66 | 2.5.1.26 | Alkyldihydroxyacetone phosphate synthase | FAD | FAD_PCMH (FAD_binding_4) | AGPS | 2q31.2 |
| 67 | 4.1.1.36 | 4’-Phosphopantothenoylcysteine decarboxylase | FMN | Flavoprotein | PPCDC | 15q24.2 |
| 68 | 4.1.99.3 | Cryptochrome | FAD | FAD-binding of DNA-photolyase | CRY1 | 12q23.3 |
| (FAD_binding_7) | CRY2 | 11p11.2 | ||||
| 69 | -------- | Apoptosis inducing protein | FAD | NADP_Rossmann (Pyr_redox_2) | AIFM1 | Xq26.1 |
| 70 | -------- | Apoptosis inducing protein | 6-OH-FAD | NADP_Rossmann (Pyr_redox_2) | AIFM2 | 10q22.1 |
| 71 | -------- | Iodotyrosine deiodinase | FMN | Nitroreductase | IYD | 6q25.1 |
| 72 | -------- | Axon guidance protein | FAD | NADP_Rossmann (FAD_binding_3) | MICAL1 | 6q21 |
| Interacting with CasL | MICAL2 | 11p15.3 | ||||
| MICAL3 | 22q11.21 | |||||
| 73 | -------- | FAD-dependent oxidoreductase (molecular chaperone of complex 1) | FAD | -------------------------------------- | FOXRED1 | 11q24.2 |
| 74 | -------- | Riboflavin transporter | Riboflavinc | -------------------------------------- | SLC52A1 | 17p13.2 |
| SLC52A2 | 8q24.3 | |||||
| SLC52A3 | 20p13 | |||||
| 75 | 1.5.1.30 | Riboflavin / FMN reductase | FMNc | NADP_Rossmann (NmrA-like) | BLVRB | 19q13.2 |
| 76 | 2.7.1.26 | Riboflavin kinase | riboflavinc | Flavokinase | RFK | 9q21.13 |
| 77 | 2.7.7.2 | FAD-adenylyl transferase (synthetase) | FMNc | HUP (PAPS_reduct) | FLAD1 | 1q21.3 |
Abbreviations used: biosyn., biosynthesis; dh, dehydrogenase; degr., degradation; dep., dependent; ER, endoplasmic reticulum; red., reductase.
⁎
Pfam classification given in plain text is for the structure of human proteins and those in italics for structures of homologs.
a
Duplicated pseudogene.
b
Opposite orientation on chromosome.
c
Substrate of transporter, modifying enzyme or reductase (entries 74–77).