3.D.2.2.2 H+-transporting NADH/NADP Transhydrogenase, PntA1 (α1)/PntA2 (α2)/PntB (β). A 3-d structure is available (Leung et al. 2015). Another structre (2.2 Å resolution) revealed conformational changes of helix positions from the previous structure solved at pH 8.5, and internal water molecules interacting with residues implicated in proton translocation. Water flows across a narrow pore and a hydrophobic "dry" region in the middle of the membrane channel, with key residues His42alpha2 (chain A) being protonated and Thr214beta (chain B) displaying a conformational change, respectively, to gate the channel access to both cytoplasmic and periplasmic chambers. Mutation of Thr214beta to Ala deactivated the enzyme (Padayatti et al. 2017).
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Accession Number: | Q72GR9 |
Protein Name: | NAD(P) transhydrogenase subunit alpha 2 |
Length: | 100 |
Molecular Weight: | 10641.00 |
Species: | Thermus thermophilus (strain HB27 / ATCC BAA-163 / DSM 7039) [262724] |
Number of TMSs: | 3 |
Substrate |
hydron |
---|
1: MEFGFWSALY IFVLTAFLGY ELITRVPVIL HTPLMSGSNF IHGVVVVGAM VVLGHAETGL
61: EKLIGFLGVI LGAANAAGGY AVTVRMLEMF ERKPGQGGGR