Electron-transporting flavoprotein or ETF (from the English electron transfer flavoprotein ) is a flavoprotein located in the inner mitochondrial membrane from the side of the matrix. It is a specific electron carrier that receives them from various dehydrogenases . It is oxidized by ETF-dehydrogenase , which transfers electrons to the respiratory chain of electron transfer . Electron-transporting flavoproteins are divided into two groups according to their functions: constitutive or “household” ETFs, which are involved in the oxidation of fatty acids (group I), and ETFs synthesized by some prokaryotes under certain conditions to obtain electrons from the oxidation of certain substrates (group II ) [1] .
| Electron Transfer Flavoprotein | |
|---|---|
 Electron-Transporting Flavoprotein (ETF) from Paracoccus denitrificans . | |
| Identifiers | |
| Symbol | ETF |
| Pfam | PF01012 |
| Pfam clan | CL0039 |
| Interpro | IPR014730 |
| PROSITE | PDOC00583 |
| SCOP | 1efv |
| SUPERFAMILY | 1efv |
| Available protein structures | |
| Pfam | the structure |
| PDB | RCSB PDB ; PDBe ; PDBj |
| PDBsum | 3D model |
| Electron-transporting flavoprotein and FAD-binding domain of trimethylamine dehydrogenase | |
|---|---|
 Electron-transporting flavoprotein from methylophilus methylotrophus . | |
| Identifiers | |
| Symbol | ETF_alpha |
| Pfam | PF00766 |
| Pfam clan | CL0085 |
| Interpro | IPR014731 |
| PROSITE | PDOC00583 |
| SCOP | 1efv |
| SUPERFAMILY | 1efv |
| Available protein structures | |
| Pfam | the structure |
| PDB | RCSB PDB ; PDBe ; PDBj |
| PDBsum | 3D model |
Electron-transporting flavoproteins are heterodimeric proteins assembled from one alpha and one beta subunit ( ETFA and ETFB ), and they contain FAD and AMP as a cofactor [2] [3] . ETFs consist of three domains : domains I and II are formed by the N- and C-terminal regions of the alpha subunit, and domain III is formed by a beta subunit. Domains I and III have a similar, almost identical α-β-α sandwich-type arrangement, and domain II has an α-β-α sandwich-type arrangement similar to that of bacterial flavodoxins . FAD is bound in the cleft between domains II and III, while domain III binds the AMP molecule. The interaction between domains I and III stabilizes the protein and creates a shallow bowl in which domain II is located.
Mutations in the electron-transporting flavoprotein lead to a lack of reduction equivalents (FADH 2 ) entering the respiratory chain of electron transfer, as well as to a violation of the decay of fatty acids and amino acids. As a result, glutaric acidemia of the second type develops.
See also
- Oxidative Phosphorylation
- Metabolism
- ETF dehydrogenase
Notes
- ↑ Weidenhaupt M., Rossi P., Beck C., Fischer HM, Hennecke H. Bradyrhizobium japonicum possesses two discrete sets of electron transfer flavoprotein genes: fixA, fixB and etfS, etfL (Eng.) // Arch. Microbiol. : journal. - 1996. - Vol. 165 , no. 3 . - P. 169-178 . - DOI : 10.1007 / s002030050312 . - PMID 8599534 .
- ↑ Tsai MH, Saier MH Phylogenetic characterization of the ubiquitous electron transfer flavoprotein families ETF-alpha and ETF-beta (Eng.) // Res. Microbiol. : journal. - 1995. - Vol. 146 , no. 5 . - P. 397-404 . - DOI : 10.1016 / 0923-2508 (96) 80285-3 . - PMID 8525056 .
- ↑ Roberts DL, Frerman FE, Kim JJ Three-dimensional structure of human electron transfer flavoprotein to 2.1-A resolution // Proceedings of the National Academy of Sciences of the United States of America : journal. - 1996. - Vol. 93 , no. 25 . - P. 14355-14360 . - DOI : 10.1073 / pnas.93.25.14355 . - PMID 8962055 .