NQR complex catalyzes the reduction of ubiquinone-1 to ubiquinol by two successive reactions, coupled with the transport of Na(+) ions from the cytoplasm to the periplasm. NqrA to nqrE are probably involved in the second step, the conversion of ubisemiquinone to ubiquinol (By similarity). PA2996 224 Na(+)-translocating NADH-quinone reductase subunit D NQRD_PSEAE nqrD NQR-1 subunit D NQR complex subunit D MMAAQPTIREVLFNPVFQNNPIGLQILGICSALAVTSNLKTATVMAIALTLVTGFSNLFISMIRRQIPSSIRMIVQMVIIASLVIVVDQVLKAYAYSLSKQLSVFVGLIITNCIVMGRAEAFAMANPPLVSFFDGIGNGLGYSAMLLVLGFVRELFGAGKLYGISVLPTVNDGGWYQPNGLLLLPPSAFFLIGLIIWALRTWKKDQVEAPTYKMAPQVSSKEAY