Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C1332347 (ADH)
 2,230 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of the various naturally occurring amino acids on ethanol oxidation in hepatocytes from starved rats was systematically studied. In order to minimize the non ADH pathways, the ethanol concentration used was 4 mmol/litre, the amino acids being added at the same concentration. In hepatocytes from fasted rats, alanine, arginine, asparagine, aspartate, citrulline, cysteine, glutamate, glutamine, glycine, histidine, hydroxyproline, ornithine and serine increase significantly ethanol consumption. The stimulatory effect of glutamine being much less pronounced than the asparagine one and proline being devoid of action, the influence of ammonium chloride addition on ethanol consumption in the presence of these amino acids was studied. Ammonium chloride determines an enhancement of ethanol oxidation in these conditions, the results showing no apparent correlation between intracellular glutamate concentration and ethanol oxidation rate, contrarily to previous data. In hepatocytes from fed rats, only alanine, asparagine, cysteine, glycine, hydroxyproline, ornithine and serine increase ethanol oxidation, although to a lesser extent than in cells from starved rats.
 ...
PMID:[Effect of natural amino acids on ethanol oxidation in isolated rat hepatocytes]. 9 50

The effects of the various naturally occurring amino acids on ethanol oxidation in hepatocytes from 18-hrs starved and fed rats were studied. In order to minimize the non-ADH pathways and to avoid interference with the liver amino acid uptake the ethanol concentration used was 4 mM, the amino acids being added at the same concentration. In hepatocytes from starved rats, asparagine, serine, ornithine, hydroxyproline, histidine, cysteine, alanine, glycine, glutamate, glutamine, aspartate and arginine significantly increase ethanol consumption. The stimulatory effect of glutamine being much less pronounced than the asparagine one and proline being devoid of action, the influence of ammonium chloride addition on ethanol consumption in the presence of these amino acids was studied. Ammonium chloride determines an enhancement of ethanol oxidation, the results showing, contrarily to previous data, no apparent correlation between intracellular glutamate concentration and ethanol oxidation rate but rather a relation with aspartate concentration. In hepatocytes from fed rats alanine, asparagine, cysteine, glycine, hydroxyproline, ornithine and serine still increase ethanol oxidation, although to a lesser extent than in cells from starved rats. It appears that only amino acids which are precursors of either pyruvate or aspartate or glutamate are able to activate the ethanol oxidation. Pyruvate, aspartate and glutamate supply malate-aspartate shuttle components especially in cells from starved rats, pyruvate allowing direct cytosolic reoxidation of NADH in cells from fed rats as well as from starved rats. The relative strengths of the stimulatory effect could be roughly dependent on energy demand for glucose synthesis in starved rats and for urea synthesis in fed rats.
 ...
PMID:Comparative study of the effect of amino acids on ethanol oxidation in isolated hepatocytes from starved and fed rats. 742 19

Biocatalysis is a promising tool for the sustainable production of chemicals. When cofactor depending enzymatic reactions are involved the applicability of the right cofactor is a central issue. One important example in this regard is the production of alcohols by nicotinamide cofactor (NAD(P)(+)) depending alcohol dehydrogenases. AdhZ3 from Escherichia coli, which is important for the production of alcohols from biomass, has a preference for NADPH as cofactor. We used a structure guided site-specific random approach, to change the cofactor preference towards NADH and to deduce more general rules for redesigning the cofactor specificity. Transfer of a triplet motif from NADH preferring horse liver ADH to AdhZ3 showed an insufficient switch in the preference towards NADH. A combinatorial site saturation mutagenesis altering three residues at once was applied. Library screening with two different cofactor concentrations (0.1 and 0.3mM) resulted in nine improved variants with AdhZ3-LND having the highest vmax and AdhZ3-CND having the lowest K(m). Asparagine was the most frequent amino acid found in eight of nine triplet motifs. To verify the triplet-motif, two variants of E. coli AdhZ2 DIN and LND were designed and confirmed for improved activity with NADH.
 ...
PMID:Improving the NADH-cofactor specificity of the highly active AdhZ3 and AdhZ2 from Escherichia coli K-12. 2499 11