Part:BBa_K4989004
Electron transfer protein beta subunit (Etfb)
The gene efb encodes for the electron transfer flavoprotein subunit beta, which creates the heterodimeric electron transfer flavoprotein (ETF), when it is joined by the electron transfer flavoprotein subunit alpha. Those subunits are the fifth and sixth Both subunits have orthologs in mammalian cells, which exist in the mitochondria and are included in various reactions. The α subunit is a precursor protein in the mitochondria, while the β subunit is expressed in the cytosol and is transferred into the mitochondria. The ETF protein is involved in the electron burification which is a mechanism to couple endergonic to exergonic redox reactions widely distributed in anaerobic bacteria. ETF creates a complex with butyryl-CoA dehydrogenase (BCD), a so-called ETF-BCD complex which was the first to be studied. This complex couples the exergonic reaction of crotonyl-CoA to butyryl-CoA by NADH with the endergonic reaction of ferredoxin. Current understanding indicates that the electron pair of NADH is split at the two-electron acceptor and one-electron donor FAD; one electron decreases the dehydrogenase FAD of Bcd and the other goes to ferredoxin (Fd), which has a low redox potential (E0′ = 405 mV). When this process is repeated, hydrogen transfer from FADH of Bcd to crotonyl-CoA results in a second decreased ferredoxin and butyryl-CoA. Two subunits make up the Etf complex from Acidaminococcus fermentans, according to structural and biochemical analyses. The α subunit coordinates one flavin adenine dinucleotide (FAD) (α-FAD), while the β subunit coordinates a second FAD (-FAD). Because NADH binds near this cofactor, the β-FAD was determined to be the location of hydride acceptance from NADH and electron bifurcation.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
| None |