PMID: 11884747 , Related PDB ids: 1KQF, 1KQG

Authors:

Jormakka M, Tornroth S, Byrne B, Iwata S

Title:

Molecular basis of proton motive force generation: structure of formate dehydrogenase-N.

Journal:

Science. 2002 Mar 8;295(5561):1863-8.

Abstract:

The structure of the membrane protein formate dehydrogenase-N (Fdn-N), a major component of Escherichia coli nitrate respiration, has been determined at 1.6 angstroms. The structure demonstrates 11 redox centers, including molybdopterin-guanine dinucleotides, five [4Fe-4S] clusters, two heme b groups, and a menaquinone analog. These redox centers are aligned in a single chain, which extends almost 90 angstroms through the enzyme. The menaquinone reduction site associated with a possible proton pathway was also characterized. This structure provides critical insights into the proton motive force generation by redox loop, a common mechanism among a wide range of respiratory enzymes.