Protein Family Models

This entry represents the N-terminal domain of Motility protein A (MotA). MotA is a membrane protein that forms the stator element of the flagellar motor complex together with MotB with 5:2 stoichiometry, which couples ion flow across the cytoplasmic membrane to generate torque, and thus, it is required for rotation of the flagellar motor. This domain contains conserved torque-generating charged residues at the C-terminal [1] and is adjacent Pfam:PF01618, which represents MotA TMH3 and TMH4. [1]. 32929189. Structures of the stator complex that drives rotation of the bacterial flagellum. Deme JC, Johnson S, Vickery O, Aron A, Monkhouse H, Griffiths T, James RH, Berks BC, Coulton JW, Stansfeld PJ, Lea SM;. Nat Microbiol. 2020;5:1553-1564. (from Pfam)

Date:

2024-10-16

This family groups together integral membrane proteins that appear to be involved translocation of proteins across a membrane. These proteins are probably proton channels. MotA is an essential component of the flageller motor that uses a proton gradient to generate rotational motion in the flageller [1]. ExbB is part of the TonB-dependent transduction complex. The TonB complex uses the proton gradient across the inner bacterial membrane to transport large molecules across the outer bacterial membrane. [1]. 10348868. Function of proline residues of MotA in torque generation by the flagellar motor of Escherichia coli. Braun TF, Poulson S, Gully JB, Empey JC, Van Way S, Putnam A, Blair DF;. J Bacteriol 1999;181:3542-3551. [2]. 9811664. Interactions in the TonB-dependent energy transduction complex: ExbB and ExbD form homomultimers. Higgs PI, Myers PS, Postle K;. J Bacteriol 1998;180:6031-6038. (from Pfam)

Date:

2024-10-16

The MotA protein, along with its partner MotB, comprise the stator complex of the bacterial flagellar motor. MotAB span the cytoplasmic membrane and undergo conformational changes powered by the translocation of protons. These conformational changes in turn are communicated to the rotor assembly, producing torque [1]. This model represents one family of MotA proteins which are often not identified by the "transporter, MotA/TolQ/ExbB proton channel family" model, PF01618.

Gene:

motA

Date:

2019-09-10

motility protein A (MotA) is a flagellar motor stator protein which is energized by a proton (H(+)) motive force

Date:

2023-03-08