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Alcohol (Fayetteville, N.Y.) Mar 2020Chronic ethanol consumption in high doses is associated with constitutively elevated activity of the serum alcohol dehydrogenase I (ADH I) isoform, which demonstrates a...
Chronic ethanol consumption in high doses is associated with constitutively elevated activity of the serum alcohol dehydrogenase I (ADH I) isoform, which demonstrates a high affinity not only for ethanol but also for a number of bioamine metabolites. Such excessive ADH activity is probably associated with disruptions in the metabolism of neurotransmitters (dopamine, serotonin, and norepinephrine) and subsequent long-term changes in the activity of their receptors. Ultimately, a stable depressive-like condition contributes to the development of patients' craving for ethanol intake, frequent disruptions during therapy, and low efficacy of treatment. We applied active immunization against ADH to investigate its efficacy in the reduction of excessive serum ADH activity and regulation of ethanol consumption by chronically ethanol-fed Wistar rats (15% ethanol, 4 months, free-choice method), and we analyzed its ability to influence the levels of bioamines in the brain. Immunization (2 injections, 2-week intervals) was performed using a combination of recombinant horse ADH isozyme as an antigen and 2% aluminum hydroxide-based adjuvant. The efficacy of immunization was demonstrated by the production of high titers of ADH-specific antibodies, which was consistent with the significantly reduced ADH activity in the serum of chronically ethanol-fed rats. On the 26th day after the first vaccine injection, we registered significantly lower levels of alcohol consumption compared to ethanol-fed control animals, and the difference reached 16% on the 49th day of the experiment. These observations were accompanied by data that showed reduced levels of ethanol preference in immunized rats. Chronic alcohol drinking led to a decrease in dopamine and DOPAL (a direct dopamine metabolite and a high-affinity ADH substrate) levels in the striatum,while immunization neutralized this effect. Additionally, we observed that inhibition of serum ADH activity caused a decrease in peak dopamine levels during acute alcohol intake in chronically ethanol-fed rats during ethanol withdrawal that was associated with reduced tyrosine hydroxylase activity in the striatum. The obtained data suggest a significant contribution of ADH to the changes in neurotransmitter systems during chronic alcohol consumption and make available new prospects for developing innovative strategies for treatment of excessive alcohol intake.
Topics: Alcohol Dehydrogenase; Alcohol Drinking; Alcoholism; Animals; Antibodies; Dopamine; Ethanol; Neurotransmitter Agents; Rats; Rats, Wistar; Vaccination
PubMed: 31260795
DOI: 10.1016/j.alcohol.2019.06.006 -
Journal of Inorganic Biochemistry Oct 2017Secondary alcohol dehydrogenase from Thermoanaerobacter brockii (TbSADH) is a Zn- and NADP-dependent enzyme that catalyses the reversible transformation of secondary...
Secondary alcohol dehydrogenase from Thermoanaerobacter brockii (TbSADH) is a Zn- and NADP-dependent enzyme that catalyses the reversible transformation of secondary alcohols into ketones. It is of potential biocatalytic interest as it can be used in the synthesis of chiral alcohols by asymmetric reduction of ketones. In this paper, density functional theory calculations are employed to elucidate the origins of the enantioselectivity of TbSADH using a large model of the active site and considering two different substrates, 2-butanol and 3-hexanol. For these two substrates the enzyme has experimentally been shown to have the opposite enantioselectivity. The energy profiles for the reactions are calculated and the stationary points along the reaction path are characterised. The calculations first confirm that the general mechanism proposed for other alcohol dehydrogenases is energetically viable. In this mechanism, a proton is first transferred from the substrate to a histidine residue at the surface, followed by a hydride transfer to the NADP cofactor. The calculated overall energy barrier is consistent with the measured rate constant. Very importantly, the calculations are able to reproduce and rationalise the enantioselectivity of the enzyme for both substrates. The detailed characterisation of the energies and geometries of the involved transition states will be valuable in the rational engineering of TbSADH to expand its utility in biocatalysis.
Topics: Alcohol Dehydrogenase; Bacterial Proteins; Butanols; Catalysis; Catalytic Domain; Coenzymes; Hexanols; NADP; Substrate Specificity; Thermoanaerobacter
PubMed: 28803132
DOI: 10.1016/j.jinorgbio.2017.07.022 -
Chembiochem : a European Journal of... Aug 2022The asymmetric reduction of ketones to chiral hydroxyl compounds by alcohol dehydrogenases (ADHs) is an established strategy for the provision of valuable precursors for...
The asymmetric reduction of ketones to chiral hydroxyl compounds by alcohol dehydrogenases (ADHs) is an established strategy for the provision of valuable precursors for fine chemicals and pharmaceutics. However, most ADHs favor linear aliphatic and aromatic carbonyl compounds, and suitable biocatalysts with preference for cyclic ketones and diketones are still scarce. Among the few candidates, the alcohol dehydrogenase from Thauera aromatica (ThaADH) stands out with a high activity for the reduction of the cyclic α-diketone 1,2-cyclohexanedione to the corresponding α-hydroxy ketone. This study elucidates catalytic and structural features of the enzyme. ThaADH showed a remarkable thermal and pH stability as well as stability in the presence of polar solvents. A thorough description of the substrate scope combined with the resolution and description of the crystal structure, demonstrated a strong preference of ThaADH for cyclic α-substituted cyclohexanones, and indicated structural determinants responsible for the unique substrate acceptance.
Topics: Alcohol Dehydrogenase; Catalysis; Ketones; Substrate Specificity; Thauera; Zinc
PubMed: 35557486
DOI: 10.1002/cbic.202200149 -
Environmental Microbiology Jan 2021Acetobacterium woodii utilizes the Wood-Ljungdahl pathway for reductive synthesis of acetate from carbon dioxide. However, A. woodii can also perform non-acetogenic...
Acetobacterium woodii utilizes the Wood-Ljungdahl pathway for reductive synthesis of acetate from carbon dioxide. However, A. woodii can also perform non-acetogenic growth on 1,2-propanediol (1,2-PD) where instead of acetate, equal amounts of propionate and propanol are produced as metabolic end products. Metabolism of 1,2-PD occurs via encapsulated metabolic enzymes within large proteinaceous bodies called bacterial microcompartments. While the genome of A. woodii harbours 11 genes encoding putative alcohol dehydrogenases, the BMC-encapsulated propanol-generating alcohol dehydrogenase remains unidentified. Here, we show that Adh4 of A. woodii is the alcohol dehydrogenase required for propanol/ethanol formation within these microcompartments. It catalyses the NADH-dependent reduction of propionaldehyde or acetaldehyde to propanol or ethanol and primarily functions to recycle NADH within the BMC. Removal of adh4 gene from the A. woodii genome resulted in slow growth on 1,2-PD and the mutant displayed reduced propanol and enhanced propionate formation as a metabolic end product. In sum, the data suggest that Adh4 is responsible for propanol formation within the BMC and is involved in redox balancing in the acetogen, A. woodii.
Topics: 1-Propanol; Acetaldehyde; Acetates; Acetobacterium; Alcohol Dehydrogenase; Aldehydes; Bacterial Proteins; Carbon Dioxide; Ethanol; Genome, Bacterial; NAD; Oxidation-Reduction
PubMed: 33283462
DOI: 10.1111/1462-2920.15340 -
BMC Genomics Jul 2020Alcohol dehydrogenases (ADHs) in plants are encoded by a multigene family. ADHs participate in growth, development, and adaptation in many plant species, but the...
BACKGROUND
Alcohol dehydrogenases (ADHs) in plants are encoded by a multigene family. ADHs participate in growth, development, and adaptation in many plant species, but the evolution and function of the ADH gene family in sugarcane is still unclear.
RESULTS
In the present study, 151 ADH genes from 17 species including 32 ADH genes in Saccharum spontaneum and 6 ADH genes in modern sugarcane cultivar R570 were identified. Phylogenetic analysis demonstrated two groups of ADH genes and suggested that these genes underwent duplication during angiosperm evolution. Whole-genome duplication (WGD)/segmental and dispersed duplications played critical roles in the expansion of ADH family in S. spontaneum and R570, respectively. ScADH3 was cloned and preferentially expressed in response to cold stress. ScADH3 conferred improved cold tolerance in E. coli cells. Ectopic expression showed that ScADH3 can also enhance cold tolerance in transgenic tobacco. The accumulation of reactive oxygen species (ROS) in leaves of transgenic tobacco was significantly lower than in wild-type tobacco. The transcript levels of ROS-related genes in transgenic tobacco increased significantly. ScADH3 seems to affect cold tolerance by regulating the ROS-related genes to maintain the ROS homeostasis.
CONCLUSIONS
This study depicted the size and composition of the ADH gene family in 17 species, and investigated their evolution pattern. Comparative genomics analysis among the ADH gene families of S. bicolor, R570 and S. spontaneum revealed their close evolutionary relationship. Functional analysis suggested that ScADH3, which maintained the steady state of ROS by regulating ROS-related genes, was related to cold tolerance. These findings will facilitate research on evolutionary and functional aspects of the ADH genes in sugarcane, especially for the understanding of ScADH3 under cold stress.
Topics: Alcohol Dehydrogenase; Cold-Shock Response; Escherichia coli; Gene Expression Regulation, Plant; Phylogeny; Saccharum
PubMed: 32727370
DOI: 10.1186/s12864-020-06929-9 -
Microbial Pathogenesis Nov 2020Acinetobacter baumannii (A. baumannii) is a common opportunistic nosocomial pathogen, which is able to produce biofilms on the surface of indwelling medical devices, and...
Acinetobacter baumannii (A. baumannii) is a common opportunistic nosocomial pathogen, which is able to produce biofilms on the surface of indwelling medical devices, and consequentially causes severe infections in clinical settings. In order to identify genes that involved in the biofilm formation of A. baumannii, the differential expression of genes between biofilms and planktonic cells was analyzed by RNAseq assay and validated in clinical isolates. The RNAseq data showed that 264 genes were up-regulated, while 240 genes were down-regulated in the biofilms of A. baumannii. Among them, the gene encoding alcohol dehydrogenase (ADH), a known molecule of bacterial quorum sensing (QS) system that plays a key role in biofilm formation bacteria, was one of the most up-regulated gene in both reference strains and clinical isolates. Functional studies using ADH inhibitor disulfiram and activator taurine further demonstrated that the presence of disulfiram significantly inhibit the cell growth, motility and biofilm formation, paralleled by a decreased expression of QS-related genes, including AbaI, A1S_0109, and A1S_0112, in a dose-dependent manner; vice versa, the addition of ADH activator taurine, and QS molecule C12- homoserine lactone synthase (HSL) led a dose-dependent increase of bacterial growth, motility and biofilm production, along with an increased expression of QS-related genes in both reference strains and clinical isolates of A. baumannii. These results suggested that the ADH was a key molecule able to modulate the QS system and promote the biofilm formation, growth and motility in A. baumannii.
Topics: Acinetobacter baumannii; Alcohol Dehydrogenase; Bacterial Proteins; Biofilms; Quorum Sensing
PubMed: 32805359
DOI: 10.1016/j.micpath.2020.104451 -
Toxicological Sciences : An Official... Aug 2018Alcohol metabolism is a well-characterized biological process that is dominated by the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) families....
Alcohol metabolism is a well-characterized biological process that is dominated by the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) families. Nonalcoholic steatohepatitis (NASH) is the advanced inflammatory stage of nonalcoholic fatty liver disease (NAFLD) and is known to alter the metabolism and disposition of numerous drugs. The purpose of this study was to investigate the alterations in alcohol metabolism processes in response to human NASH progression. Expression and function of ADHs, ALDHs, and catalase were examined in normal, steatosis, NASH (fatty) and NASH (not fatty) human liver samples. ALDH4A1 mRNA was significantly decreased in both NASH groups, while no significant changes were observed in the mRNA levels of other alcohol-related enzymes. The protein levels of ADH1A, ADH1B, and ADH4 were each decreased in the NASH groups, which was consistent with a decreased overall ADH activity. The protein level of ALDH2 was significantly increased in both NASH groups, while ALDH1A1 and ALDH1B1 were only decreased in NASH (fatty) samples. ALDH activity represented by oxidation of acetaldehyde was decreased in the NASH (fatty) group. The protein level of catalase was decreased in both NASH groups, though activity was unchanged. Furthermore, the significant accumulation of 4-hydroxynonenal protein adduct in NASH indicated significant oxidative stress and a potential reduction in ALDH activity. Collectively, ADH and ALDH expression and function are profoundly altered in the progression of NASH, which may have a notable impact on ADH- and ALDH-associated cellular metabolism processes and lead to significant alterations in drug metabolism mediated by these enzymes.
Topics: Alcohol Dehydrogenase; Aldehyde Dehydrogenase; Disease Progression; Ethanol; Humans; Isoenzymes; Liver; Non-alcoholic Fatty Liver Disease; Polymorphism, Single Nucleotide; RNA, Messenger
PubMed: 29718361
DOI: 10.1093/toxsci/kfy106 -
Progress in Biophysics and Molecular... May 2017The behaviors of simple thermal systems have been well studied in physical chemistry and the principles obtained from such studies have been applied to complex thermal... (Review)
Review
The behaviors of simple thermal systems have been well studied in physical chemistry and the principles obtained from such studies have been applied to complex thermal systems, such as proteins and enzymes. But the simple application of such principles is questionable and may lead to mistakes under some circumstances. In enzymology, the transition state theory of chemical reactions has been accepted as a fundamental theory, but the role of protein dynamics in enzyme catalysis is controversial in the context of transition state theory. By studying behaviors of complex thermal systems, we have revised the Arrhenius equation and transition state theory and our model is validated in enzymology. Formally speaking, the revised Arrhenius equation is apparently similar to a conventional Arrhenius equation, but the physical meanings of its parameters differ from that of traditional forms in principle. Within this model, the role of protein dynamics in enzyme catalysis is well defined and quantified.
Topics: Alcohol Dehydrogenase; Enzymes; Models, Biological; Protein Conformation; Protein Folding; Proteins
PubMed: 28163054
DOI: 10.1016/j.pbiomolbio.2017.02.001 -
Current Medicinal Chemistry 2016Despite long and intensive investigation, the mechanisms by which nitric oxide (NO) regulates immune function and carcinogenesis remain incompletely understood. Protein... (Review)
Review
Despite long and intensive investigation, the mechanisms by which nitric oxide (NO) regulates immune function and carcinogenesis remain incompletely understood. Protein S-nitrosylation, the covalent attachment of a nitroso group to a cysteine thiol, has emerged as a central mechanism of NO-dependent cellular regulation. In particular, recent research has revealed important roles for S-nitrosylation/denitrosylation in modulating the activity of macrophage and tumor cell proteins, implicating Snitrosylation in the regulation of macrophage function as well as in tumor development and response to therapy. This review summarizes recent progress in the identification and characterization of S-nitrosylated proteins in macrophages and cancer cells. The review highlights key findings and insights obtained from functional and proteomic studies about the roles of S-nitrosylation in signaling, transcription, apoptosis and other cellular processes relevant to macrophage function and cancer progression. Some of the implications of recent discoveries for the development of novel anticancer approaches are also discussed.
Topics: Alcohol Dehydrogenase; Animals; Glutathione; Humans; Macrophages; Neoplasms; Nitric Oxide; Protein Processing, Post-Translational; Receptor Protein-Tyrosine Kinases; Thioredoxins
PubMed: 27356534
DOI: 10.2174/0929867323666160627114839 -
Journal of the American Chemical Society May 2020Two obstacles limit the application of oxidoreductase-based asymmetric synthesis. One is the consumption of high stoichiometric amounts of reduced cofactor. The other is...
Two obstacles limit the application of oxidoreductase-based asymmetric synthesis. One is the consumption of high stoichiometric amounts of reduced cofactor. The other is the low solubility of organic substrates, intermediates, and products in the aqueous phase. In order to address these two obstacles to oxidoreductase-based asymmetric synthesis, a biphasic bioelectrocatalytic system was constructed and applied. In this study, the preparation of chiral β-hydroxy nitriles catalyzed by alcohol dehydrogenase (AdhS) and halohydrin dehalogenase (HHDH) was investigated as a model bioelectrosynthesis, since they are high-value intermediates in statin synthesis. Diaphorase (DH) was immobilized by a cobaltocene-modified poly(allylamine) redox polymer on the electrode surface (DH/-PAA bioelectrode) to achieve effective bioelectrocatalytic NADH regeneration. Since AdhS is a NAD-dependent dehydrogenase, the diaphorase-modified biocathode was used to regenerate NADH to support the conversion from ethyl 4-chloroacetoacetate (COBE) to ethyl ()-4-chloro-3-hydroxybutanoate (()-CHBE) catalyzed by AdhS. The addition of methyl -butyl ether (MTBE) as an organic phase not only increased the uploading of COBE but also prevented the spontaneous hydrolysis of COBE, extended the lifetime of DH/-PAA bioelectrode, and increased the Faradaic efficiency and the concentration of generated ()-ethyl-4-cyano-3-hydroxybutyrate (()-CHCN). After 10 h of reaction, the highest concentration of ()-CHCN in the biphasic bioelectrocatalytic system was 25.5 mM with 81.2% enantiomeric excess (). The conversion ratio of COBE achieved 85%, which was 8.8 times higher than that achieved with the single-phase system. Besides COBE, two other substrates with aromatic ring structures were also used in this biphasic bioelectrocatalytic system to prepare the corresponding chiral β-hydroxy nitriles. The results indicate that the biphasic bioelectrocatalytic system has the potential to produce a variety of β-hydroxy nitriles with different structures.
Topics: Alcohol Dehydrogenase; Biocatalysis; Electrochemical Techniques; Hydrolases; Molecular Structure; Nitriles
PubMed: 32286819
DOI: 10.1021/jacs.0c01890