1E3I

Mouse class II alcohol dehydrogenase complex with NADH and inhibitor

Summary for 1E3I

• Entry DOI: 10.2210/pdb1e3i/pdb
• Descriptor: ALCOHOL DEHYDROGENASE, CLASS II, 1,4-DIHYDRONICOTINAMIDE ADENINE DINUCLEOTIDE, CYCLOHEXYLFORMAMIDE, ... (5 entities in total)
• Functional Keywords: oxidoreductase
• Biological source: MUS MUSCULUS (HOUSE MOUSE)
• Cellular location: Cytoplasm : Q9QYY9
• Total number of polymer chains: 2
• Total formula weight: 82035.72

Authors

Svensson, S.,Hoog, J.O.,Schneider, G.,Sandalova, T. (deposition date: 2000-06-16, release date: 2000-09-12, Last modification date: 2023-12-13)

Primary citation

Svensson, S.,Hoeoeg, J.O.,Schneider, G.,Sandalova, T.
Crystal Structure of Mouse Class II Alcohol Dehydrogenase Reveal Determinants of Substrate Specificity and Catalytic Efficiency
J.Mol.Biol., 302:441-, 2000

PubMed Abstract: The structure of mouse class II alcohol dehydrogenase (ADH2) has been determined in a binary complex with the coenzyme NADH and in a ternary complex with both NADH and the inhibitor N-cyclohexylformamide to 2.2 A and 2.1 A resolution, respectively. The ADH2 dimer is asymmetric in the crystal with different orientations of the catalytic domains relative to the coenzyme-binding domains in the two subunits, resulting in a slightly different closure of the active-site cleft. Both conformations are about half way between the open apo structure and the closed holo structure of horse ADH1, thus resembling that of ADH3. The semi-open conformation and structural differences around the active-site cleft contribute to a substantially different substrate-binding pocket architecture as compared to other classes of alcohol dehydrogenase, and provide the structural basis for recognition and selectivity of alcohols and quinones. The active-site cleft is more voluminous than that of ADH1 but not as open and funnel-shaped as that of ADH3. The loop with residues 296-301 from the coenzyme-binding domain is short, thus opening up the pocket towards the coenzyme. On the opposite side, the loop with residues 114-121 stretches out over the inter-domain cleft. A cavity is formed below this loop and adds an appendix to the substrate-binding pocket. Asp301 is positioned at the entrance of the pocket and may control the binding of omega-hydroxy fatty acids, which act as inhibitors rather than substrates. Mouse ADH2 is known as an inefficient ADH with a slow hydrogen-transfer step. By replacing Pro47 with His, the alcohol dehydrogenase activity is restored. Here, the structure of this P47H mutant was determined in complex with NADH to 2.5 A resolution. His47 is suitably positioned to act as a catalytic base in the deprotonation of the substrate. Moreover, in the more closed subunit, the coenzyme is allowed a position closer to the catalytic zinc. This is consistent with hydrogen transfer from an alcoholate intermediate where the Pro/His replacement focuses on the function of the enzyme.

PubMed: 10970744
DOI: 10.1006/JMBI.2000.4039

Experimental method

X-RAY DIFFRACTION (2.08 Å)