1KB0

Crystal Structure of Quinohemoprotein Alcohol Dehydrogenase from Comamonas testosteroni

Summary for 1KB0

• Entry DOI: 10.2210/pdb1kb0/pdb
• Descriptor: quinohemoprotein alcohol dehydrogenase, CALCIUM ION, HEME C, ... (7 entities in total)
• Functional Keywords: beta-propeller fold, cytochrome c, oxidoreductase
• Biological source: Comamonas testosteroni
• Cellular location: Periplasm (Potential): Q46444
• Total number of polymer chains: 1
• Total formula weight: 74819.65

Authors

Rozeboom, H.J.,Oubrie, A. (deposition date: 2001-11-05, release date: 2001-12-28, Last modification date: 2024-11-20)

Primary citation

Oubrie, A.,Rozeboom, H.J.,Kalk, K.H.,Huizinga, E.G.,Dijkstra, B.W.
Crystal structure of quinohemoprotein alcohol dehydrogenase from Comamonas testosteroni: structural basis for substrate oxidation and electron transfer.
J.Biol.Chem., 277:3727-3732, 2002

PubMed Abstract: Quinoprotein alcohol dehydrogenases are redox enzymes that participate in distinctive catabolic pathways that enable bacteria to grow on various alcohols as the sole source of carbon and energy. The x-ray structure of the quinohemoprotein alcohol dehydrogenase from Comamonas testosteroni has been determined at 1.44 A resolution. It comprises two domains. The N-terminal domain has a beta-propeller fold and binds one pyrroloquinoline quinone cofactor and one calcium ion in the active site. A tetrahydrofuran-2-carboxylic acid molecule is present in the substrate-binding cleft. The position of this oxidation product provides valuable information on the amino acid residues involved in the reaction mechanism and their function. The C-terminal domain is an alpha-helical type I cytochrome c with His(608) and Met(647) as heme-iron ligands. This is the first reported structure of an electron transfer system between a quinoprotein alcohol dehydrogenase and cytochrome c. The shortest distance between pyrroloquinoline quinone and heme c is 12.9 A, one of the longest physiological edge-to-edge distances yet determined between two redox centers. A highly unusual disulfide bond between two adjacent cysteines bridges the redox centers. It appears essential for electron transfer. A water channel delineates a possible pathway for proton transfer from the active site to the solvent.

PubMed: 11714714
DOI: 10.1074/jbc.M109403200

Experimental method

X-RAY DIFFRACTION (1.44 Å)