Biochemical aspects of the interaction of ethanol with barbiturates

1970 ◽  
Vol 48 (6) ◽  
pp. 706-711 ◽  
Author(s):  
H. Locksley Trenholm ◽  
William B. Maxwell ◽  
Charles J. Paul ◽  
G. Stuart Wiberg ◽  
Blake B. Coldwell
Keyword(s):  
Alcohol Dehydrogenase ◽  
Enzymatic Activity ◽  
Ammonium Sulfate ◽  
Hepatic Tissue ◽  
Alcohol Metabolism ◽  
Ammonium Sulfate Precipitation ◽  
Tissue Slices ◽  
Catalyzed Oxidation ◽  
Oxidation Of Ethanol

When pentobarbital is added to a hepatic supernatant enzyme fraction which contains alcohol dehydrogenase from a rat, the rates of the enzyme-catalyzed oxidation of ethanol and reduction of acetaldehyde are increased. The pentobarbital enhancement of enzymatic activity which is dependent on pentobarbital concentration is still observed when the enzyme is purified by column chromatography on DEAE- and CM-Sephadex and ammonium sulfate precipitation. In in vitro studies where hepatic tissue slices were incubated with alcohol, pentobarbital inhibited the metabolism of alcohol and increased the acetaldehyde levels in the incubation mixture. The addition of 32.5 mM NAD resulted in a return of alcohol metabolism and acetaldehyde concentrations to control levels.

Kinetics of Alcohol Dehydrogenase-Catalyzed Oxidation of Ethanol Followed by Visible Spectroscopy

2005 ◽  
Vol 82 (7) ◽  
pp. 1068 ◽  
Author(s):  
Kestutis Bendinskas ◽  
Christopher DiJiacomo ◽  
Allison Krill ◽  
Ed Vitz
Keyword(s):  
Alcohol Dehydrogenase ◽  
Visible Spectroscopy ◽  
Kinetics Of ◽  
Catalyzed Oxidation ◽  
Oxidation Of Ethanol

scholarly journals Effects of Ozone Oxidative Preconditioning on TNF-αRelease and Antioxidant-Prooxidant Intracellular Balance in Mice During Endotoxic Shock

2005 ◽  
Vol 2005 (1) ◽  
pp. 16-22 ◽  
Author(s):  
Zullyt B. Zamora ◽  
Aluet Borrego ◽  
Orlay Y. López ◽  
René Delgado ◽  
Ricardo González ◽  
...  
Keyword(s):  
Glutathione Peroxidase ◽  
Enzymatic Activity ◽  
Redox State ◽  
Endotoxic Shock ◽  
Gaseous Mixture ◽  
Hepatic Tissue ◽  
Mouse Serum ◽  
Antioxidant Systems ◽  
Dependent Manner

Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of cell redox state by the increase of antioxidant endogenous systems in both in vivo and in vitro experimental models. Our aim is to analyze the effect of ozone oxidative preconditioning on serum TNF-αlevels and as a modulator of oxidative stress on hepatic tissue in entodoxic shock model (mice treated with lipopolysaccharide (LPS)). Ozone/oxygen gaseous mixture which was administered intraperitoneally (0.2,0.4, and1.2mg/kg) once daily for five days before LPS (0.1mg/kg, intraperitoneal). TNF-αwas measured by cytotoxicity on L-929 cells. Biochemical parameters such as thiobarbituric acid reactive substances (TBARS), enzymatic activity of catalase, glutathione peroxidase, and glutathione-S transferase were measured in hepatic tissue. One hour after LPS injection there was a significant increase in TNF-αlevels in mouse serum. Ozone/oxygen gaseous mixture reduced serum TNF-αlevels in a dose-dependent manner. Statistically significant decreases in TNF-αlevels after LPS injection were observed in mice pretreated with ozone intraperitoneal applications at0.2(78%),0.4(98%), and1.2(99%). Also a significant increase in TBARS content was observed in the hepatic tissue of LPS-treated mice, whereas enzymatic activity of glutathion-S transferase and glutathione peroxidase was decreased. However in ozone-treated animals a significant decrease in TBARS content was appreciated as well as an increase in the activity of antioxidant enzymes. These results indicate that ozone oxidative preconditioning exerts inhibitory effects on TNF-αproduction and on the other hand it exerts influence on the antioxidant-prooxidant balance for preservation of cell redox state by the increase of endogenous antioxidant systems.

Hemophilia: Modified by a Post-Exercise Plasminogen Activator

1975 ◽  
Author(s):  
J. W. Hampton ◽  
A. Weidenbach ◽  
G. E. Skye ◽  
C. Rubenstein ◽  
F. B. Taylor
Keyword(s):  
Factor Viii ◽  
Plasminogen Activator ◽  
Ammonium Sulfate ◽  
Degradation Products ◽  
Genetic Disorder ◽  
Factor Viii Activity ◽  
Ammonium Sulfate Precipitation ◽  
Excessive Bleeding ◽  
Post Exercise

A family with 9 members of both sexes in 4 generations was demonstrated to have enhanced fibrinolysis associated with excessive bleeding. Three with the worst bleeding, all males, had 10% Factor VIII activity (high antigen, bleeding time normal and ristocetin platelet aggregation normal) with no male to male transmission. Antiplasmin proteins, α-I antitrypsin and α-2 macroglobulin were present and functionally normal. Inconsistently elevated fibrin degradation products, low fibrinogen and short euglobulin lysis times first suggested that a plasminogen activator might be present and enhanced by physical activity. Epsilon amino caproic acid (4 gms/day) given to one member with low Factor VIII inhibited the plasma activator but his Factor VIII activity only rose from 10 to 30%. In 2 affected members tested after exercise the activator activity increased up to 10-fold and required exogenous plasminogen for its demonstration. Ammonium sulfate precipitation (35-45% ) of the post-exercise plasma was pH, temperature and concentration dependent and again required exogenous plasminogen. At optimal conditions for plasminogen activation plasmin was obtained with the ammonium sulfate precipitation. Chromatography of the precipitate on Sephadex G-200 showed separation of the activator from both plasminogen and fibrinogen. The protein showed no reaction with an anti-urokinase on double-immunodiffusion and did not require Hageman fragments for its activation. We conclude that the Factor VIII deficiency in this family more closely resembles classic hemophilia and that exercise-induced activator excess modifies the expression of the genetic disorder. The presence of the activator is not Factor VIII dependent since the addition of Factor VIII in vitro did not inhibit the activation of plasminogen.

scholarly journals Inhibition of microsomal oxidation of ethanol by pyrazole and 4-methylpyrazole in vitro Increased effectiveness after induction by pyrazole and 4-methylpyrazole

1986 ◽  
Vol 239 (3) ◽  
pp. 671-677 ◽  
Author(s):  
D E Feierman ◽  
A I Cederbaum
Keyword(s):  
Alcohol Dehydrogenase ◽  
Ethanol Oxidation ◽  
Liver Microsomes ◽  
Chronic Ethanol ◽  
Ethanol Metabolism ◽  
Ethanol Treatment ◽  
Previously Treated ◽  
Kinetics Of ◽  
Oxidation Of Ethanol

Pyrazole and 4-methylpyrazole, which are inhibitors of alcohol dehydrogenase, were also found to be effective inhibitors of the oxidation of ethanol by liver microsomes (microsomal fractions) in vitro. Ethanol oxidation by microsomes from rats previously treated for 2 or 3 days with either pyrazole or 4-methylpyrazole appeared to be especially sensitive to inhibition in vitro by pyrazole or 4-methylpyrazole. The kinetics of inhibition by pyrazole or 4-methylpyrazole in all microsomal preparations were mixed, as the Km for ethanol was elevated while Vmax was lowered. However, Ki values for pyrazole (about 0.35 mM) and especially 4-methylpyrazole (about 0.03-0.10 mM) were much lower than those found with the saline controls (about 0.7-1.1 mM). In contrast, Ki values for dimethyl sulphoxide as an inhibitor of microsomal ethanol oxidation were similar in all microsomal preparations. Pyrazole and 4-methylpyrazole reacted with microsomes to produce type II spectral changes whose magnitude increased after treatment with either pyrazole or 4-methylpyrazole. Thus the increased inhibitory effectiveness of pyrazole and 4-methylpyrazole appears to be associated with increased interactions with the cytochrome P-450 isoenzyme(s) induced by these compounds. These isoenzymes have properties similar to those of the isoenzyme induced by chronic ethanol treatment. Therefore, caution is needed in the use of pyrazole or 4-methylpyrazole to assess pathways of ethanol metabolism, especially after chronic ethanol treatment, since these agents, besides inhibiting alcohol dehydrogenase, are also effective inhibitors of microsomal ethanol oxidation.

The Paradoxical Effect of Alcohol on Carbohydrate Metabolism in Four Patients with Liver Glycogen Disease

PEDIATRICS ◽  
1965 ◽  
Vol 35 (6) ◽  
pp. 1005-1008
Author(s):  
CHARLES U. LOWE ◽  
LUIS L. MOSOVICH
Keyword(s):  
Amino Acids ◽  
Alcohol Dehydrogenase ◽  
Carbohydrate Metabolism ◽  
Liver Glycogen ◽  
Paradoxical Effect ◽  
Alcohol Metabolism ◽  
Lactate Levels ◽  
Coupled Reaction ◽  
Oxidation Of Ethanol

Oxidation of ethanol to acetaldehyde, the first step in alcohol metabolism, is catalyzed by the enzyme alcohol dehydrogenase and resuits in the reduction of DPN to DPNH. In a coupled reaction, pyruvate is converted to lactate with regeneration to DPN. There are a number of consequences of these reactions when alcohol is consumed. Lactate levels in blood rise; DPNH produced by the reaction inhibits the enzymatic steps involved in the conversion of UDP galactose to UDP glucose and glutamate to alpha keto glutarate. As a result of these inhibitions, galactose removal from blood is markedly delayed and gluconeogenesis from amino acids is inhibited.

Extraction and Partial Purification of Protease from Bilimbi (Averrhoa bilimbi L.)

2013 ◽  
Vol 10 (2) ◽  
pp. 29
Author(s):  
Normah Ismail ◽  
Nur' Ain Mohamad Kharoe
Keyword(s):  
Molecular Weight ◽  
Protein Content ◽  
Ammonium Sulfate ◽  
Molecular Weight Distribution ◽  
Weight Distribution ◽  
Protease Activity ◽  
Protein Concentration ◽  
Temperature Stability ◽  
Partial Purification ◽  
Ammonium Sulfate Precipitation

Unripe and ripe bilimbi (Averrhoa bilimbi L.) were ground and the extracted juices were partially purified by ammonium sulfate precipitation at the concentrations of 40 and 60% (w/v). The collected proteases were analysed for pH, temperature stability, storage stability, molecular weight distribution, protein concentration and protein content. Protein content of bilimbi fruit was 0.89 g. Protease activity of both the unripe and ripe fruit were optimum at pH 4 and 40°C when the juice were purified at 40 and 60% ammonium sulfate precipitation. A decreased in protease activity was observed during the seven days of storage at 4°C. Molecular weight distribution indicated that the proteases protein bands fall between IO to 220 kDa. Protein bands were observed at 25, 50 and 160 kDa in both the unripe and ripe bilimbi proteases purified with 40% ammonium sulfate, however, the bands were more intense in those from unripe bilimbi. No protein bands were seen in proteases purified with 60% ammonium sulfate. Protein concentration was higher for proteases extracted with 40% ammonium sulfate at both ripening stages. Thus, purification using 40% ammonium sulfate precipitation could be a successful method to partially purify proteases from bilimbi especially from the unripe stage. 

Kinase Targets for Mycolic Acid Biosynthesis in Mycobacterium tuberculosis

2019 ◽  
Vol 12 (1) ◽  
pp. 27-49 ◽  
Author(s):  
Shahinda S.R. Alsayed ◽  
Chau C. Beh ◽  
Neil R. Foster ◽  
Alan D. Payne ◽  
Yu Yu ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Enzymatic Activity ◽  
Bacterial Pathogen ◽  
Building Blocks ◽  
Mycolic Acid ◽  
Adaptive Responses ◽  
Mycolic Acids ◽  
Hydroxylated Fatty Acids

Background:Mycolic acids (MAs) are the characteristic, integral building blocks for the mycomembrane belonging to the insidious bacterial pathogen Mycobacterium tuberculosis (M.tb). These C60-C90 long α-alkyl-β-hydroxylated fatty acids provide protection to the tubercle bacilli against the outside threats, thus allowing its survival, virulence and resistance to the current antibacterial agents. In the post-genomic era, progress has been made towards understanding the crucial enzymatic machineries involved in the biosynthesis of MAs in M.tb. However, gaps still remain in the exact role of the phosphorylation and dephosphorylation of regulatory mechanisms within these systems. To date, a total of 11 serine-threonine protein kinases (STPKs) are found in M.tb. Most enzymes implicated in the MAs synthesis were found to be phosphorylated in vitro and/or in vivo. For instance, phosphorylation of KasA, KasB, mtFabH, InhA, MabA, and FadD32 downregulated their enzymatic activity, while phosphorylation of VirS increased its enzymatic activity. These observations suggest that the kinases and phosphatases system could play a role in M.tb adaptive responses and survival mechanisms in the human host. As the mycobacterial STPKs do not share a high sequence homology to the human’s, there have been some early drug discovery efforts towards developing potent and selective inhibitors.Objective:Recent updates to the kinases and phosphatases involved in the regulation of MAs biosynthesis will be presented in this mini-review, including their known small molecule inhibitors.Conclusion:Mycobacterial kinases and phosphatases involved in the MAs regulation may serve as a useful avenue for antitubercular therapy.

scholarly journals PenA, a penicillin-binding protein-type thioesterase specialized for small peptide cyclization

2021 ◽  
Author(s):  
Kenichi Matsuda ◽  
Kei Fujita ◽  
Toshiyuki Wakimoto
Keyword(s):  
Enzymatic Activity ◽  
Computational Model ◽  
Binding Protein ◽  
Penicillin Binding Protein ◽  
Small Peptide ◽  
Peptide Cyclization ◽  
Chain Lengths ◽  
Non Ribosomal Peptides

Abstract Penicillin binding protein-type thioesterases (PBP-type TEs) are a recently identified group of peptide cyclases that catalyze head-to-tail macrolactamization of non-ribosomal peptides. PenA, a new member of this group, is involved in the biosyntheses of cyclic pentapeptides. In this study, we demonstrated the enzymatic activity of PenA in vitro, and analyzed its substrate scope with a series of synthetic substrates. A comparison of the reaction profiles between PenA and SurE, a representative PBP-type TE, showed that PenA is more specialized for small peptide cyclization. A computational model provided a possible structural rationale for the altered specificity for substrate chain lengths.

scholarly journals A set of simple methods for detection and extraction of laminarinase

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ananthamurthy Koteshwara ◽  
Nancy V. Philip ◽  
Jesil Mathew Aranjani ◽  
Raghu Chandrashekhar Hariharapura ◽  
Subrahmanyam Volety Mallikarjuna
Keyword(s):  
Ammonium Sulfate ◽  
Ammonium Sulphate ◽  
Gold Standard ◽  
Direct Detection ◽  
Low Cost ◽  
Direct Analysis ◽  
Reducing Sugar ◽  
Ammonium Sulfate Precipitation ◽  
Simple Method ◽  
Functional Step

AbstractA carefully designed ammonium sulfate precipitation will simplify extraction of proteins and is considered to be a gold standard among various precipitation methods. Therefore, optimization of ammonium sulfate precipitation can be an important functional step in protein purification. The presence of high amounts of ammonium sulphate precludes direct detection of many enzymatically active proteins including reducing sugar assays (e.g. Nelson-Somogyi, Reissig and 3,5-dinitrosalicylic acid methods) for assessing carbohydrases (e.g. laminarinase (β (1–3)-glucanohydrolase), cellulases and chitinases). In this study, a simple method was developed using laminarin infused agarose plate for the direct analysis of the ammonium sulphate precipitates from Streptomyces rimosus AFM-1. The developed method is simple and convenient that can give accurate results even in presence of ammonium sulfate in the crude precipitates. Laminarin is a translucent substrate requiring the use of a stain to visualize the zones of hydrolysis in a plate assay. A very low-cost and locally available fluorescent optical fabric brightener Tinopal CBS-X has been used as a stain to detect the zones of hydrolysis. We also report simple methods to prepare colloidal chitin and cell free supernatant in this manuscript.

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