Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Target Concepts:
Gene/Protein
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Enzyme
Compound
Query: EC:1.1.1.1 (
alcohol dehydrogenase
)
9,284
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Pyrazole and 4-methylpyrazole (4-MP) are potent, effective inhibitors of
alcohol dehydrogenase
. Pyrazole and its derivatives also have been shown to affect the cytochrome P-450 dependent monooxygenase system. This study was performed to investigate the effect of 4-MP on the disposition kinetics of antipyrine (AP). Groups of male Fisher 344 rats were given an ip injection of 4-MP (100 mg/kg) or 4-MP
HCl
(equivalent to 4-MP 100 mg/kg) or an equivalent volume of saline. AP (20 mg/kg) was injected intravenously via the jugular vein catheter 30 minutes later. Blood samples were collected upto 24 hours and assayed by HPLC. 4-MP pretreatment significantly decreased AP clearance from 0.490 +/- 0.032 to 0.095 +/- 0.014 (4-MP
HCl
) and 0.076 +/- 0.008 (4-MP) L/hr.kg (p less than 0.01). The volume of distribution of AP decreased from 0.82 +/- 0.07 to 0.65 +/- 0.06 (4-MP
HCl
) and 0.56 +/- 0.04 (4-MP) L/kg (p less than 0.05). Mean residence time increased from 1.68 +/- 0.09 to 6.91 +/- 0.58 (4-MP
HCl
) and 7.39 +/- 0.56 (4-MP) hr (p less than 0.01). These results demonstrate a significant inhibitory effect of 4-MP on the cytochrome P-450 isozyme(s) which is responsible for AP metabolism in intact animals.
...
PMID:Inhibitory effect of 4-methylpyrazole on antipyrine clearance in rats. 174 Sep 74
The potential and limitations in scaling-up free-flow electrophoresis, with emphasis on zone electrophoresis, are demonstrated. Purification of
alcohol dehydrogenase
(
ADH
) from a crude yeast extract was chosen as a model for an industrial approach to enzyme purification. In zone electrophoresis the separation quality strongly depends on the pH and conductivity of the background electrolyte, its residence time and flow rate, as well as the applied voltage. Optimization of these parameters resulted in a purification factor of 5.3 and a yield of 96%
ADH
, using a Tris/
HCl
buffer, pH 8.0, and a conductivity of 1 mS/cm, with a residence time of 10 min at 500 V. The loading capacity of the method for a laboratory-sized free-flow electrophoresis apparatus was limited to a sample throughput of about 0.4 g/h. By increasing the chamber dimensions it was possible to purify the enzyme by a purification factor of 4.7 and a yield of 93%
ADH
, at a throughput of about 1 g total protein/h. By simultaneously applying the sample at 3 input positions the throughput could be increased to 2.75 g/h with a purification factor of 4.7 and an overall yield of 90%.
...
PMID:Scale-up of free flow electrophoresis: I. Purification of alcohol dehydrogenase from a crude yeast extract by zone electrophoresis. 220 46
Nonporous agarose beads, prepared by shrinkage and cross-linking in organic solvents, were derivatized with Cibacron Blue F3G-A. A compressed bed of these beads was used for purification of dehydrogenases (glucose-6-phosphate dehydrogenase, lactate dehydrogenase and
alcohol dehydrogenase
). The chromatographic conditions for the purification of glucose-6-phosphate dehydrogenase were optimized by varying the pH of the buffer; the concentrations of eluting agents, i.e. NADP (specific elution) and sodium chloride (nonspecific elution); flow rate; residence time of the protein on the column bed; and protein load. Specific elution with NADP (2 mM in 0.025 M Tris-
HCl
, pH 8.0) gave the highest recovery (140%) and highest purification factor (200-fold) of the enzyme. The ability of the compressed bed of nonporous agarose beads to tolerate high flow rates was essential, since the recovery of the enzyme activity increased with an increase in flow rate.
...
PMID:High-performance liquid chromatography of proteins on deformed nonporous agarose beads. Affinity chromatography of dehydrogenases based on cibacron blue-derivatized agarose. 223 11
Biochemical and histological studies on the effect of separate and combined administration of LiCl and of chlorpromazine (CPZ) on female C57BL/6J mice were performed. Mice were divided into 4 groups. One group was given an intraperitoneal injection daily of CPZ
HCl
, 5 mg/kg for 4 days followed by 4 more days of a daily dosage of 10 mg/kg. A second group was maintained on 0.4% (w/v) LiCl solution as the sole drinking fluid for 8 consecutive days and a third group received the same LiCl solution but with daily CPZ injection as the initial group for 8 days. The fourth group served as saline-controls. Hepatic liver
alcohol dehydrogenase
was induced by combined drug treatment from respective controls. The Li-treatment inhibited mitochondrial liver aldehyde dehydrogenase, and coadministration of CPZ with LiCl antagonized this effect. Mice treated with CPZ showed corneal cellularity and mitotic figure appearance without inflammation. The LiCl treated mice displayed variations in base corneal cell size, shape and pigmentation with aggregation of the nuclei, and the presence of mitotic activity inflammation. Mice receiving combined drug treatment showed similar corneal alterations, but mitotic figures were found above base cell layer suggesting an enhanced corneal toxicity. The results suggest a drug-drug interaction phenomenon which may explain some of their adverse reaction when given concurrently.
...
PMID:Chlorpromazine and lithium interaction: a biochemical and histological study. 631 43
Alcohol dehydrogenase was purified in 14 h from male Fischer-344 rat livers by differential centrifugation, (NH4)2SO4 precipitation, and chromatography over DEAE-Affi-Gel Blue, Affi-Gel Blue, and AMP-agarose. Following HPLC more than 240-fold purification was obtained. Under denaturing conditions, the enzyme migrated as a single protein band (Mr congruent to 40,000) on 10% sodium dodecyl sulfate-polyacrylamide gels. Under nondenaturing conditions, the protein eluted from an HPLC I-125 column as a symmetrical peak with a constant enzyme specific activity. When examined by analytical isoelectric focusing, two protein and two enzyme activity bands comigrated closely together (broad band) between pH 8.8 and 8.9. The pure enzyme showed pH optima for activity between 8.3 and 8.8 in buffers of 0.5 M Tris-
HCl
, 50 mM 2-(N-cyclohexylamino)ethanesulfonic acid (CHES), and 50 mM 3-(cyclohexylamino)-1-propanesulfonic acid (CAPS), and above pH 9.0 in 50 mM glycyl-glycine. Kinetic studies with the pure enzyme, in 0.5 M Tris-
HCl
under varying pH conditions, revealed three characteristic ionization constants for activity: 7.4 (pK1); 8.0-8.1 (pK2), and 9.1 (pK3). The latter two probably represent functional groups in the free enzyme; pK1 may represent a functional group in the enzyme-NAD+ complex. Pure enzyme also was used to determine kinetic constants at 37 degrees C in 0.5 M Tris-
HCl
buffer, pH 7.4 (I = 0.2). The values obtained were Vmax = 2.21 microM/min/mg enzyme, Km for ethanol = 0.156 mM, Km for NAD+ = 0.176 mM, and a dissociation constant for NAD+ = 0.306 mM. These values were used to extrapolate the forward rate of ethanol oxidation by
alcohol dehydrogenase
in vivo. At pH 7.4 and 10 mM ethanol, the rate was calculated to be 2.4 microM/min/g liver.
...
PMID:Rat liver alcohol dehydrogenase. I. Purification and characterization. 635 85
Human liver
alcohol dehydrogenase
(
ADH
) isoenzymes beta 1 beta 1, gamma 1 gamma 1 from Caucasian individuals with 'typical'
ADH
and beta 2 beta 2-Bern from Caucasian individuals with 'atypical' phenotype differed in their susceptibility to anions. At pH 7.0 beta 1 beta 1 and gamma 1 gamma 1 were more active in Tris-
HCl
buffer than in sodium phosphate buffer but less active in Hepes-NaOH and Mops-NaOH. beta 2 beta 2-Bern showed the same activity in all these buffers. At pH 7.0 and at low concentrations (50-100 mM) chloride activated the ethanol oxidation by beta 1 beta 1 and gamma 1 gamma 1, whereas sulfate showed no effect. At anion concentrations above 100 mM all isoenzymes were inhibited. At pH 10.5 beta 1 beta 1 and gamma 1 gamma 1 were not activated. Measuring the acetaldehyde reduction, no comparable activation by chloride was observed; all three isoenzymes were inhibited, at significantly lower anion concentrations. These anion effects can be correlated with the different primary structures of the isoenzymes around the active site and the coenzyme binding site.
...
PMID:Differential susceptibility of human alcohol dehydrogenase isoenzymes to anions. 639 57
A new method was developed for the estimation of arginine vasopressin (AVP) in plasma and urine. Samples were extracted by a microcolumn of resin and assayed radioimmunologically using a highly sensitive antiserum to AVP. Ion-exchange resin, CG-50, H+ form, packed in a small column (diameter 4 mm, height 6 mm), was proved effective to remove the interfering substances and to concentrate the AVP in the sample. The application of 80% acid acetone successive to diluted
HCl
brought about a consistent recovery of AVP from the resin column. Recoveries were 66.4 +/- 8.5% for plasma and 85.4 +/- 9.7% for urine. In normal subjects plasma AVP levels were 3.9 +/ 0.3 pg/ml (mean +/- S.D.) in ambulatory states, 4.9 +/- ).6 after overnight fast, and 0.4 +/- 0.2 after water lading. High levels of 2.0 +/- 24.2 pg/ml were obtained in patinents with syndrome of inappropriate secretion of
ADH
(SIADH), low values of 0-1.8 pg/ml in diabetes inipidus. Urinary excretions of AVP were 117.4 +/- 59.4 ng/24/hr (mean +/- S.D.) in normal controls, 191 +/- 177.0/24 hr in SIADH, and 17.0 +/- 12.0/24 hr in diabetes insipidus.
...
PMID:Radioimmunoassay of arginine vasopressin in human plasma and urine, a resin microcolumn method. 740 74
The coenzyme specificity of horse liver
alcohol dehydrogenase
assayed in mixtures of acetonitrile and buffer, 0.01 M Tris/
HCl
pH 7.4, was investigated. The enzyme could accept NADP+ as coenzyme if it was first bio-imprinted with NADP+, i.e. precipitated from an aqueous buffer with 1-propanol in the presence of NADP+ dried, and then assayed in a system with less than 10% buffer. When assayed in a system with 25% buffer, no activity with NADP+ as coenzyme was observed. The activity was measured with a coenzyme regeneration assay with cinnamoyl alcohol and octylaldehyde as substrates. Other methods to prepare a binary complex of horse liver
alcohol dehydrogenase
and NADP+, i.e. if the enzyme was immobilized on silica and NADP+ added afterwards or if it was deposited on Celite together with NADP+, failed to show any bio-imprinting effect. The activity of horse liver
alcohol dehydrogenase
bioimprinted with NADP+ and assayed in acetonitrile/buffer mixtures with less than 10% buffer showed the same or higher activity than an enzyme preparation prepared by bio-imprinting with NAD+. The hypothesis is that the conformation of the active site of horse liver
alcohol dehydrogenase
is modified to one that is complementary to the ligand present during precipitation and drying. This is possible because of the restricted motility of the enzyme conformation in high concentrations of organic solvent. In the presence of more than 10% buffer the mobility increases in such a way that the imposed conformation with activity towards NADP+ disappears.
...
PMID:Horse liver alcohol dehydrogenase can accept NADP+ as coenzyme in high concentrations of acetonitrile. 785 36
Acetaldehyde, propionaldehyde, glyceraldehyde-3-P and 4-dimethylaminocinnamaldehyde form Schiff bases in Tris.
HCl
buffers; the rates of formation and dissociation of Schiff bases, and equilibrium constants for their formation are very similar for the first three aldehydes. The steady-state kinetic constants for the
yeast alcohol dehydrogenase
-catalyzed reaction, propan-1-ol + NAD+ reversible propionaldehyde + NADH + H+, have been determined in several Tris.
HCl
buffers of increasing concentration at pH 8.1. In the forward direction, oxidation of alcohol, most kinetic constants are increased by increasing concentrations of Tris. In the reverse direction, reduction of aldehyde, substrate, NADH, Tris and Schiff base were equilibrated before enzyme reaction was started. It was found that Schiff base, rather than Tris, binds to free enzyme competitively with respect to NADH. Tris and Schiff base do not influence the binding of aldehyde to enzyme in any way.
...
PMID:Influence of Tris(hydroxymethyl)aminomethane on kinetic mechanism of yeast alcohol dehydrogenase. 987 14
A rapid method for screening potential dye ligands for use in affinity chromatography is described. Textile dyes were non-covalently coupled to a cross-linked polysaccharide Sepharose(R) matrix. Yeast
alcohol dehydrogenase
(
ADH
) was used as the model protein for evaluating the screening system. A homogenate from baker's yeast was used as the crude source of enzyme. Batchwise adsorption and elution were used to evaluate the individual dyes. The influence of pH and ionic strength in the binding and elution steps was evaluated. Batch isotherms were used to evaluate parameter characteristics. Experimental data obtained were fitted to Langmuir isotherms to determine the maximum binding capacity and the dissociation constant for each dye evaluated in this study. A dynamic binding capacity of 107.6 units of
ADH
/g of resin was determined for Procion Turquoise MXG dye by frontal analysis. Specific elution with NAD+ and non-specific elution with 50 mM Tris/
HCl
buffer, pH 8.5, were tested when Procion Turquoise MXG was used, giving purification factors of 53.5 and 4.4 respectively. This screening technique is inexpensive and can be performed in a few hours. It was possible to predict the performance of different reactive dyes in this way, and the influence of pH and salt on the binding behaviour was demonstrated.
...
PMID:Rapid screening of textile dyes employed as affinity ligands to purify enzymes from yeast. 1007 11
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