TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*3.D.2.1.1









H+-translocating transhydrogenase
Bacteria
Proteobacteria
α2β2 heterotetrameric PTH of E. coli
*3.D.2.2.1









H+-translocating transhydrogenase
Bacteria
Proteobacteria
(α1)2(α2)2β2 heterohexameric PTH of Rhodospirillum rubrum
*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).

Bacteria
Deinococcus-Thermus
Transhydrogenase of Thermus thermophilus
α1 subunit of 375 aas (Q72GR8)
α2 subunit of 100 aas (Q72GR9)
β subunit of 450 aas (Q72GS0)
*3.D.2.3.1









H+-translocating transhydrogenase
Eukaryota
Metazoa
Homodimeric PTH of Bos taurus
*3.D.2.4.1









H+-translocating transhydrogenase
Eukaryota
Apicomplexa
PTH of Eimeria tenella