>cd00581 QFR_TypeB_TM Quinol:fumarate reductase (QFR) Type B subfamily, transmembrane subunit; QFR couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, the opposite reaction to that catalyzed by the related protein, succinate:quinone oxidoreductase (SQR). QFRs oxidize low potential quinols such as menaquinol and rhodoquinol and are involved in anaerobic respiration with fumarate as the terminal electron acceptor. SQR and QFR share a common subunit arrangement, composed of a flavoprotein catalytic subunit, an iron-sulfur protein and one or two hydrophobic transmembrane subunits. Members of this subfamily are classified as Type B as they contain one transmembrane subunit and two heme groups. The heme and quinone binding sites reside in the transmembrane subunit. The structural arrangement allows efficient electron transfer between the catalytic subunit, through iron-sulfur centers, and the transmembrane subunit containing the electron donor (quinol). The

Probab=94.70  E-value=0.19  Score=27.28  Aligned_cols=62  Identities=15%  Similarity=0.125  Sum_probs=32.9

Q ss_pred             HHHHHHHHHHHHHHHHHHHHHHHCCCHHHHHHHHHC---------CCHHHHHHHHHHHHHHHHHHHHHHHH
Q ss_conf             999999999999999999998516303554675306---------83169999999999999999989999
Q gi|254781041|r   30 RITGSVVYLGTPVVVFWFFCIANGEHTLSSLRCYMD---------GSVFEVCLFLYTWAVIHHMLGGIRYL   91 (129)
Q Consensus        30 RitGi~l~~~~~~~~~~l~~~~~~~~~~~~~~~~~~---------~~~~k~~~~~~~~~~~yH~~nGiRHL   91 (129)
T Consensus         6 s~TGl~LalFm~~Hm~fvSSILlg~~a~~~va~f~E~~~~~~~g~p~v~~~~~~~I~~~f~~Ha~lA~RK~   76 (206)
T cd00581           6 SATGLFLALFMWAHMLFVSSILLGKEAMYWVARFFEGAFFFGHGYPWVVSVVAAIVFALFVAHAFLALRKF   76 (206)
T ss_pred             HHHHHHHHHHHHHHHHHHHHHHCCHHHHHHHHHHHHHHHCCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHC
T ss_conf             88899999999999999999971899999999998510302788448999999999999999999999866