PubMed HealthSearch

PubMed · 8493926

Class IV alcohol dehydrogenase: structure and function.

Abstract

The source did not provide an abstract. Follow the original record for more information.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

X Parés, J Farrés, A Moreno, N Saubi, M D Boleda, E Cederlund, J O Höög, H Jörnvall. 1993. Class IV alcohol dehydrogenase: structure and function.. https://doi.org/10.1007/978-1-4615-2904-0_50

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

A Raman spectroscopic characterization of bonding in the complex of horse liver alcohol dehydrogenase with NADH and N-cyclohexylformamide.

The binding of N-cyclohexylformamide (CXF) to the complex of horse liver alcohol dehydrogenase with NADH mimics that of the Michaelis complex for aldehyde reduction catalyzed by the enzyme. The Raman spectra of bound CXF and its 13C- and 15N-substituted derivatives have been obtained using Raman difference techniques, and the results are compared with CXF spectra in aqueous solution and in methylene chloride. The results indicate that the amide N-H bond is trans to the C=O bond of CXF both in solution and in the enzyme ternary complex. The C=O stretch and N-H bending modes of the amide of CXF shift -16 and -9 cm-1, respectively, in the enzyme ternary complex relative to that in aqueous solution and -48 and 36 cm-1, respectively, relative to that in methylene chloride. Ab initio normal mode calculations on various model systems of CXF show that the observed frequency changes of the C=O stretch mode have contributions from the frequency changes induced by the environmental changes near both the local C=O bond and the remote N-H bond. The same is true for the observed N-H bending frequency change. Our calculations also show that the environmentally induced frequency changes are additive so that it is possible to determine the C=O stretch (or N-H bending) frequency change that is due to the local interaction change near the C=O (or N-H) bond from the observed frequency changes. On the basis of these results and the empirical relationship between the C=O stretch frequency shift and the interaction enthalpy change on the C=O bond developed here, it is found that the C=O group of CXF in the enzyme/NADH/CXF complex binds with a favorable interaction enthalpy of approximately 5.5 kcal/mol relative to water. Similar analysis suggests that the N-H moiety of CXF is destabilized in the ternary complex by about 1.5 kcal/mol relative to water but is stabilized by about 1.5 kcal/mol relative to a hydrophobic environment. The analysis describes quantitatively the binding of the C=O of CXF with the catalytic zinc and the hydroxyl group of Ser-48 and the interaction of the N-H with the benzene ring of Phe-93 of the enzyme.

Alcohol Dehydrogenase

An attempt to transform class characteristics within the alcohol dehydrogenase family.

Human class I alcohol dehydrogenase was mutated at positions 57 and 115, exchanging for Asp and Arg respectively, in an attempt to introduce glutathione-dependent formaldehyde dehydrogenase characteristics. In addition, class III alcohol dehydrogenase, identical to glutathione-dependent formaldehyde dehydrogenase, was mutated at position 115, introducing Ser or Lys. The attempted class transformation was partly successful considering a higher affinity for 12-hydroxydodecanoate and a lower affinity for ethanol that was monitored for the class I mutant. However, the class I mutant displayed neither glutathione-dependent formaldehyde dehydrogenase activity nor fatty acid activation of alcohol oxidation. Interestingly, both class III mutants showed reduced activities for S-hydroxymethylglutathione and 12-hydroxydodecanoate through increased Km, values. Overall results show that it is not possible, by single point mutations, to completely transform enzyme characteristics between these two classes of alcohol dehydrogenase.

Alcohol Dehydrogenase

The refined crystal structure of Drosophila lebanonensis alcohol dehydrogenase at 1.9 A resolution.

Drosophila alcohol dehydrogenase (DADH; EC 1.1.1.1) is a NAD(H)-dependent oxidoreductase belonging to the short-chain dehydrogenases/reductases (SDR) family. This homodimeric enzyme catalyzes the dehydrogenation of alcohols to their respective ketones or aldehydes in the fruit-fly Drosophila, both for metabolic assimilation and detoxification purposes. The crystal structure of the apo form of DADH, one of the first biochemically characterized member of the SDR family, was solved at 1.9 A resolution by Patterson methods. The initial model was improved by crystallographic refinement accompanied by electron density averaging, R-factor=20.5%, R-free=23.8%.DADH subunits show an alpha/beta single domain structure with a characteristic NAD(H) binding motif (Rossmann fold). The peptide chain of a subunit is folded into a central eight-stranded beta-sheet flanked on each side by three alpha-helices. The dimers have local 2-fold symmetry. Dimer association is dominated by a four-helix bundle motif as well as two C-terminal loops from each subunit, which represent a unique structural feature in SDR enzymes with known structure. Three structural features are characteristic for the active site architecture. (1) A deep cavity which is covered by a flexible loop (33 residues) and the C-terminal tail (11 residues) from the neighboring subunit. The hydrophobic surface of the cavity is likely to increase the specificity of this enzyme towards secondary aliphatic alcohols. (2) The residues of the catalytic triad (Ser138, Tyr151, Lys155) are known to be involved in enzymatic catalysis in the first line. The Tyr151 OH group is involved in an ionic bond with the Lys155 side-chain. Preliminary electrostatic calculations have provided evidence that the active form of Tyr151 is a tyrosinate ion at physiological pH. (3) Three well-ordered water molecules in hydrogen bond distance to side-chains of the catalytic triad may be significant for the proton release steps in DADH catalysis.A ternary structure-based sequence alignment with ten members of the SDR family with known three-dimensional structure has suggested to define a model consisting of four groups of residues, which relates the observed low degree of sequence identity to quite similar folding patterns and nearly identical distributions of residues involved in catalysis.

Alcohol Dehydrogenase