>TIGR01144 ATP_synt_b ATP synthase F0, B subunit; InterPro: IPR005864 ATPases (or ATP synthases) are membrane-bound enzyme complexes/ion transporters that combine ATP synthesis and/or hydrolysis with the transport of protons across a membrane. ATPases can harness the energy from a proton gradient, using the flux of ions across the membrane via the ATPase proton channel to drive the synthesis of ATP. Some ATPases work in reverse, using the energy from the hydrolysis of ATP to create a proton gradient. There are different types of ATPases, which can differ in function (ATP synthesis and/or hydrolysis), structure (F-, V- and A-ATPases contain rotary motors) and in the type of ions they transport , . F-ATPases (F1F0-ATPases) in mitochondria, chloroplasts and bacterial plasma membranes are the prime producers of ATP, using the proton gradient generated by oxidative phosphorylation (mitochondria) or photosynthesis (chloroplasts). V-ATPases (V1V0-ATPases) are primarily found in eukaryotic vacuoles, catalysing ATP hydrolysis to transport solutes and lower pH in organelles. A-ATPases (A1A0-ATPases) are found in Archaea and function like F-ATPases. P-ATPases (E1E2-ATPases) are found in bacteria and in eukaryotic plasma membranes and organelles, and function to transport a variety of different ions across membranes. E-ATPases are cell-surface enzymes that hydrolyse a range of NTPs, including extracellular ATP. F-ATPases (also known as F1F0-ATPase, or H(+)-transporting two-sector ATPase) (3.6.3.14 from EC) are composed of two linked complexes: the F1 ATPase complex is the catalytic core and is composed of 5 subunits (alpha, beta, gamma, delta, epsilon), while the F0 ATPase complex is the membrane-embedded proton channel that is composed of at least 3 subunits (A-C), nine in mitochondria (A-G, F6, F8). Both the F1 and F0 complexes are rotary motors that are coupled back-to-back. In the F1 complex, the central gamma subunit forms the rotor inside the cylinder made of the alpha(3)beta(3) subunits, while in the F0 complex, the ring-shaped C subunits forms the rotor. The two rotors rotate in opposite directions, but the F0 rotor is usually stronger, using the force from the proton gradient to push the F1 rotor in reverse in order to drive ATP synthesis . These ATPases can also work in reverse to hydrolyse ATP to create a proton gradient. This entry represents subunit B from the F0 complex in F-ATPases found in bacterial plasma membranes. The B subunits are part of the peripheral stalk that links the F1 and F0 complexes together, and which acts as a stator to prevent certain subunits from rotating with the central rotary element. The peripheral stalk differs in subunit composition between mitochondrial, chloroplast and bacterial F-ATPases. In bacterial F-ATPases, the peripheral stalk is composed of one copy of the delta subunit (homologous to OSCP in mitochondria), and two copies of subunit B . More information about this protein can be found at Protein of the Month: ATP Synthases .; GO: 0046933 hydrogen ion transporting ATP synthase activity rotational mechanism, 0046961 hydrogen ion transporting ATPase activity rotational mechanism, 0015986 ATP synthesis coupled proton transport, 0016469 proton-transporting two-sector ATPase complex.

Probab=97.54  E-value=0.0054  Score=35.96  Aligned_cols=136  Identities=9%  Similarity=0.083  Sum_probs=103.1

Q ss_pred             HHHHHHHHHHHHHHHHHHHHHH-------HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
Q ss_conf             9999999999999999996228-------899999999999999999999999999999999999999999999999999
Q gi|254781085|r    6 TFLVFMSLIIFLVIVVYLRIPS-------ILLSFLDAHADKIRDDIFEARRLREKSENILMQYKEKHSKVEEETREIILA   78 (173)
Q Consensus         6 tfw~~i~f~il~~il~~~~~~~-------~i~~~l~~R~~~I~~~l~~A~~~~~~a~~~~~~~~~~l~~a~~ea~~i~~~   78 (173)
T Consensus         4 ~F~llv~f~~---KY~w~Pl~~~~~~R~~~IA~~L~~AE~~~~~~~~~~~~~~~~l~~AK~~A~~ii~~A~k~~~~~~ee   80 (147)
T TIGR01144         4 SFILLVWFCK---KYVWPPLAKAIETRQKKIADDLASAERAKKEAALAQKEAQVLLKEAKDEAQEIIENANKRGSEILEE   80 (147)
T ss_pred             HHHHHHHHHH---HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
T ss_conf             9999999998---8623799999998899859889999998888999998988999988888889999987888886999


Q ss_pred             HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCHHHHHHHHHH
Q ss_conf             9999999999999999999999999999999999999999999999999999999999943399999999999
Q gi|254781085|r   79 AKHRAKILAEEGCQNIEQISALYLKDLEQKIHYMKLEAKRLLYAKIADFSVEIVREIISQKMNDDVNSSIFEK  151 (173)
Q Consensus        79 a~~~a~~~~e~~~~~a~~~~~~~~~~a~~~I~~~~~~a~~~l~~~~~~la~~~~~kil~~~l~~~~~~~~I~~  151 (173)
T Consensus        81 ~~~~A~~e~~ki~~~A~~EI~~~~~~Ar~~Lr-------~~Va~L~V~~AeKii~~~iD~~~~~d~id~~~~~  146 (147)
T TIGR01144        81 IKAEAREEREKILASARAEIEAEKERAREELR-------KQVADLAVAGAEKIIEREIDKQAQKDLIDKLVAE  146 (147)
T ss_pred             HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH-------HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
T ss_conf             99998988999999884459999999999999-------9999999999999998878999988899998731