1r27
From Proteopedia
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Crystal Structure of NarGH complex
Overview
The structure of the catalytic and electron-transfer subunits (NarGH) of, the integral membrane protein, respiratory nitrate reductase (Nar) has, been determined to 2.0 A resolution revealing the molecular architecture, of this Mo-bisMGD (molybdopterin-guanine-dinucleotide) containing enzyme, which includes a previously undetected FeS cluster. Nar, together with the, related enzyme formate dehydrogenase (Fdh-N), is a key enzyme in the, generation of proton motive force across the membrane in Escherichia coli, nitrate respiration. A comparative study revealed that Nar and Fdh-N, employ different approaches for acquiring substrate, reflecting different, catalytic mechanisms. Nar uses a very narrow and nonpolar, substrate-conducting cavity with a nonspecific substrate binding site, whereas Fdh-N accommodates a wider, positively charged, substrate-conducting cavity with a more specific substrate binding site., The Nar structure also demonstrates the first example of an Asp side chain, acting as a Mo ligand providing a structural basis for the classification, of Mo-bisMGD enzymes.
About this Structure
1R27 is a Protein complex structure of sequences from Escherichia coli with MO, F3S, SF4 and MGD as ligands. Active as Nitrate reductase, with EC number 1.7.99.4 Full crystallographic information is available from OCA.
Reference
Architecture of NarGH reveals a structural classification of Mo-bisMGD enzymes., Jormakka M, Richardson D, Byrne B, Iwata S, Structure. 2004 Jan;12(1):95-104. PMID:14725769
Page seeded by OCA on Wed Nov 21 01:13:04 2007
