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Gluconobacter oxydans succinic semialdehyde reductase (GoxSSAR) and Acetobacter aceti glyoxylate reductase (AacGR) represent a novel class in the β-hydroxyacid dehydrogenases superfamily. Kinetic analyses revealed GoxSSAR's activity with both glyoxylate and succinic semialdehyde, while AacGR is glyoxylate specific. GoxSSAR K167A lost activity with succinic semialdehyde but retained some with glyoxylate, whereas AacGR K175A lost activity. These findings elucidate differences between these homologous enzymes. [ABSTRACT FROM AUTHOR]

Gluconobacter strains perform incomplete oxidation of various sugars and alcohols, employing regio- and stereoselective membrane-bound dehydrogenases oriented toward the periplasmic space. This oxidative fermentation process is utilized industrially. The ketogluconate production pathway, characteristic of these strains, begins with the conversion of d -glucose to d -gluconate, which then diverges and splits into 2 pathways producing 5-keto- d -gluconate and 2-keto- d -gluconate and subsequently 2,5-diketo- d -gluconate. These transformations are facilitated by membrane-bound d -glucose dehydrogenase, glycerol dehydrogenase, d -gluconate dehydrogenase, and 2-keto- d -gluconate dehydrogenase. The variance in end products across Gluconobacter strains stems from the diversity of enzymes and their activities. This review synthesizes biochemical and genetic knowledge with biotechnological applications, highlighting recent advances in metabolic engineering and the development of an efficient production process focusing on enzymes relevant to the ketogluconate production pathway in Gluconobacter strains. [ABSTRACT FROM AUTHOR]

Oxidative stress and autophagy are potential mechanisms associated with cerebral ischemia/reperfusion injury (IRI) and is usually linked to inflammatory responses and apoptosis. Curcumin has recently been demonstrated to exhibit anti-inflammatory, antioxidant, anti-apoptotic and autophagy regulation properties. However, mechanism of curcumin on IRI-induced oxidative stress and autophagy remains not well understood. We evaluated the protective effects and potential mechanisms of curcumin on cerebral microvascular endothelial cells (bEnd.3) and neuronal cells (HT22) against oxygen glucose deprivation/reoxygenation (OGD/R) in vitro models that mimic in vivo cerebral IRI. The cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) activity assays revealed that curcumin attenuated the OGD/R-induced injury in a dose-specific manner. OGD/R induced elevated levels of inflammatory cytokines TNF-α, IL-6 as well as IL-1β, and these effects were notably reduced by curcumin. OGD/R-mediated apoptosis was suppressed by curcumin via upregulating B-cell lymphoma-2 (Bcl-2) and downregulating Bcl-associated X (Bax), cleaved-caspase3 and TUNEL apoptosis marker. Additionally, curcumin increased superoxide dismutase (SOD) and glutathione (GSH), but suppressed malondialdehyde (MDA) and reactive oxygen species (ROS) content. Curcumin inhibited the levels of autophagic biomarkers such as LC3 II/LC3 I and Beclin1. Particularly, curcumin induced p62 accumulation and its interactions with keap1 and promoted NF-E2-related factor 2 (Nrf2) translocation to nucleus, accompanied by increased NADPH quinone dehydrogenase (Nqo1) and heme oxygenase 1 (HO-1). Treatment of curcumin increased phosphorylationphosphatidylinositol 3 kinase (p-PI3K) and p-protein kinase B (p-AKT). The autophagy inhibitor 3-methyladenine (3-MA) activated the keap-1/Nrf2 and PI3K/AKT pathways. This study highlights the neuroprotective effects of curcumin on cerebral IRI. [ABSTRACT FROM AUTHOR]

Reprogramming of energy metabolism is one of the basic characteristics of cancer and has been proved to be an important cancer treatment strategy. Isocitrate dehydrogenases (IDHs) are a class of key proteins in energy metabolism, including IDH1, IDH2, and IDH3, which are involved in the oxidative decarboxylation of isocitrate to yield α -ketoglutarate (α -KG). Mutants of IDH1 or IDH2 can produce d -2-hydroxyglutarate (D-2HG) with α -KG as the substrate, and then mediate the occurrence and development of cancer. At present, no IDH3 mutation has been reported. The results of pan-cancer research showed that IDH1 has a higher mutation frequency and involves more cancer types than IDH2 , implying IDH1 as a promising anti-cancer target. Therefore, in this review, we summarized the regulatory mechanisms of IDH1 on cancer from four aspects: metabolic reprogramming, epigenetics, immune microenvironment, and phenotypic changes, which will provide guidance for the understanding of IDH1 and exploring leading-edge targeted treatment strategies. In addition, we also reviewed available IDH1 inhibitors so far. The detailed clinical trial results and diverse structures of preclinical candidates illustrated here will provide a deep insight into the research for the treatment of IDH1-related cancers. Isocitrate dehydrogenase 1 (IDH1) is a potential target for cancer treatment. Mutant IDH1 promotes the occurrence and development of cancer by influencing metabolism, immune microenvironment, epigenetics, and phenotype. [Display omitted] [ABSTRACT FROM AUTHOR]

Dithiocarbamates have been widely used in various industrial applications, such as insecticides (ferbam) or drug (disulfiram). This study explored the inhibitory effects of dithiocarbamates on human and rat gonadal 3β-hydroxysteroid dehydrogenases (3β-HSD) and investigated the structure-activity relationship and mechanistic insights. The inhibitory activity of six dithiocarbamates and thiourea on the conversion of pregnenolone to progesterone was evaluated using human KGN cell and rat testicular microsomes, with subsequent progesterone measurement using HPLC-MS/MS. The study found that among the tested compounds disulfiram, ferbam, and thiram exhibited significant inhibitory activity against human 3β-HSD2 and rat 3β-HSD1, with ferbam demonstrating the highest potency. The mode of action for these compounds was characterized, showing mixed inhibition for human 3β-HSD2 and mixed/noncompetitive inhibition for rat 3β-HSD1. Additionally, it was observed that dithiothreitol dose-dependently reversed the inhibitory effects of dithiocarbamates on both human and rat gonadal 3β-HSD enzymes. The study also delved into the penetration of these dithiocarbamates through the human KGN cell membrane and their impact on progesterone production, highlighting their potency in inhibiting human 3β-HSD2. Furthermore, bivariate correlation analysis revealed a positive correlation of LogP (lipophilicity) with IC 50 values for both enzymes. Docking analysis indicated that dithiocarbamates bind to NAD+ and steroid-binding sites, with some interactions with cysteine residues. In conclusion, this study provides valuable insights into the structure-activity relationship and mechanistic aspects of dithiocarbamates as inhibitors of human and rat gonadal 3β-HSDs, suggesting that these compounds likely exert their inhibitory effects through binding to cysteine residues. [Display omitted] • Some dithiocarbamates inhibit human and rat gonadal 3β-HSDs. • Ferbam is the most potent inhibitor of both human and rat gonadal 3β-HSD. • Dithiocarbamates are mixed/noncompetitive inhibitors of gonadal 3β-HSDs. • DTT can reverse dithiocarbamate-mediated inhibition on 3β-HSDs. • Lipophilicity determines the inhibitory potency of dithiocarbamates on 3β-HSDs. [ABSTRACT FROM AUTHOR]

We identiied a novel lavoprotein--cytochrome c complex d-gluconate dehydrogenase (GADH) encoded by gndXYZ of Gluconobacter oxydans NBRC 3293, which is phylogenetically distinct from previously reported GADHs encoded by gndFGH and gndSLC of Gluconobacter spp. To analyze the biochemical properties of respective GADHs, Gluconobacter japonicus NBRC 3271 mutant strain lacking membranous d-gluconate dehydrogenase activity was constructed. All GADHs (GndFGH, GndSLC, and GndXYZ) were successfully overexpressed in the constructed strain. The optimal pH and KM value at that pH of GndFGH, GndSLC, and GndXYZ were 5, 6, and 4, and 8.82 ± 1.15, 22.9 ± 5.0, and 11.3 ± 1.5 mm, respectively.When the mutants overexpressing respective GADHs were cultured in d-glucose-containing medium, all of them produced 2-keto-d-gluconate, revealing that GndXYZ converts d-gluconate to 2-keto-d-gluconate as well as other GADHs. Among the recombinants, the gndXYZ-overexpressing strain accumulated the highest level of 2-keto-d-gluconate, suggesting its potential for 2-keto-d-gluconate production. [ABSTRACT FROM AUTHOR]

Formate dehydrogenases catalyze the reversible oxidation of formate to carbon dioxide. These enzymes play an important role in CO 2 reduction and serve as nicotinamide cofactor recycling enzymes. More recently, the CO 2 -reducing activity of formate dehydrogenases, especially metal-containing formate dehydrogenases, has been further explored for efficient atmospheric CO 2 capture. In this sense, molecular hydrogen (H 2) as the fuel of the future represents an efficient, cheap and environmentally friendly reducing agent when produced from renewable sources. Hydrogenases are enzymes that catalyze the reversible oxidation of H 2. Herein, the functional interplay between the soluble [NiFe] hydrogenase from Cupriavidus necator and the molybdenum-dependent formate dehydrogenase from Rhodobacter capsulatus was investigated in a coupled biocatalytic system. H 2 -driven CO 2 reduction (H 2 CO 2 R) using methyl viologen as an artificial electron mediator gave a higher product yield of formate than using NAD+ as the physiological electron mediator. The enzymes were stable under anaerobic conditions for 18 h, making the coupled reaction suitable for biotechnological purposes. • The interaction between C. necator [NiFe] hydrogenase and R. capsulatus Mo-dependent formate dehydrogenase was investigated. • H 2 -driven CO 2 reduction (H 2 CO 2 R) using methyl viologen as an artificial electron mediator was very efficient. • The enzymes were stable under anaerobic conditions for 18 h. • The described cascade reaction is suitable for biotechnological purposes. [ABSTRACT FROM AUTHOR]

Malaria still threatens global health seriously today. While the current discoveries of antimalarials are almost totally focused on single mode-of-action inhibitors, multi-targeting inhibitors are highly desired to overcome the increasingly serious drug resistance. Here, we performed a structure-based drug design on mitochondrial respiratory chain of Plasmodium falciparum and identified an extremely potent molecule, RYL-581, which binds to multiple protein binding sites of P. falciparum simultaneously (allosteric site of type II NADH dehydrogenase, Q o and Q i sites of cytochrome bc 1). Antimalarials with such multiple targeting mechanism of action have never been reported before. RYL-581 kills various drug-resistant strains in vitro and shows good solubility as well as in vivo activity. This structure-based strategy for designing RYL-581 from starting compound may be helpful for other medicinal chemistry projects in the future, especially for drug discovery on membrane-associated targets. A highly potent antimalarial compound, RYL-581, has a potential multi-targeting mechanism of action by simultaneously binding to three pockets (allosteric site of Pf NDH2, Q o and Q i sites of Pf bc 1). [Display omitted] [ABSTRACT FROM AUTHOR]

Juvenile hormone III (JH III) plays an important role in insect reproduction, development, and behavior. The second branch of JH III production includes oxidation of farnesol to farnesal by farnesol dehydrogenase. This study reported the identification and characterization of Plutella xylostella farnesol dehydrogenase (PxFoLDH). Our results showed that PxFoLDH belongs to the short-chain dehydrogenase/reductase superfamily, consisting of a single domain with a structurally conserved Rossman fold, an NAD(P) (H)-binding region and a structurally diverse C-terminal region. The purified enzyme displayed maximum activity at 55 |$\ $| °C with pH 9.5 and was stable in the temperature below 70 |$\ ^\circ $| C. PxFoLDH was determined to be a monomer with a relative molecular weight of 27 kDa and highly specific for trans, trans- farnesol, and NADP+. Among analog inhibitors tested, farnesyl acetate was the most effective inhibitor with the lowest  K i value of 0.02 µ m. Our findings showed this purified enzyme may represent as NADP+-farnesol dehydrogenase. [ABSTRACT FROM AUTHOR]

The enzymatic activity of soil was studied in a three-year pot experiment, where different amounts of zinc were introduced: 0, 200, 400, and 600 mg of Zn kg-1 of soil, as well as organic materials (control object, bovine manure, laying hens’ litter, spent mushroom substrate), used separately with the soil application dose of 2 g Corg kg-1 soil. Zinc and organic materials were used once, only in the first year of research, before sowing the test plant. In each year of the experiment, the test plant was orchard grass (Dactylis glomerata L.), harvested after 4 cuts. The activity of urease, dehydrogenases, as well as acid and alkaline phosphatase were determined in the soil collected after the last grass cutting, in each year of the study. Application of zinc to soil, regardless of its dose, resulted in a decrease in the activity of urease, dehydrogenase and alkaline phosphatase, although the significance of differences in relation to the control object was demonstrated only at higher doses, such as 400 and 600 mg Zn kg-1 soil. The study showed no negative effect of zinc on acid phosphatase activity. Organic fertilizers generally resulted in an increase in the enzymatic activity of the analyzed soil, and simultaneously limited the negative effects of higher zinc doses (400 and 600 mg Zn kg-1 of soil) on urease and dehydrogenase activity. During the consecutive years, urease and alkaline phosphatase activity decreased, while acid phosphatase activity increased. Dehydrogenase activity did not change significantly in the subsequent years of the study. [ABSTRACT FROM AUTHOR]

Catathelasmols C, D, and E, which had been isolated from Catathelasma imperiale as inhibitors for 11-hydroxysteroid dehydrogenases, were comprehensively semisynthesized from commercially available D-glutamic acid. The key synthetic intermediate, (R)-pentane-1,2,5-triol, was site-selectively acetylated by treatment with vinyl acetate and Candida antarctica lipase B (Novozym 435) in tetrahydrofuran (THF) at 25°C to furnish 1,5-diacetate (catathelasmol E, quantitative). The acetylation occurred site-selectively on the primary alcohols at the C-1 and C-5 positions over the secondary alcohol at the C-2 position. Dichromic acid oxidation provided 2-oxopentane-1,5-diyl diacetate (catathelasmol C, 78%). Burkholderia cepacia lipase-catalyzed transesterification with methanol in THF at – 5°C proceeded preferentially on the acetate at C-1 located adjacent to the C-2 carbonyl group over the other terminal acetate at the C-5 position. 5-Hydroxy-4-oxopentyl acetate (catathelasmol D) was obtained in 53% yield. Catathelasmols (C, D, and E), inhibitors for 11-hydroxysteroid dehydrogenases, were comprehensively semisynthesized from commercially available D-glutamic acid. Key steps: lipase-catalyzed site-selective acylation and deacetylation [ABSTRACT FROM AUTHOR]

The enzymatic activity of soil was studied in a three-year pot experiment, where different amounts of zinc were introduced: 0, 200, 400, and 600 mg of Zn kg-1 of soil, as well as organic materials (control object, bovine manure, laying hens' litter, spent mushroom substrate), used separately with the soil application dose of 2 g Corg kg-1 soil. Zinc and organic materials were used once, only in the first year of research, before sowing the test plant. In each year of the experiment, the test plant was orchard grass (Dactylis glomerata L.), harvested after 4 cuts. The activity of urease, dehydrogenases, as well as acid and alkaline phosphatase were determined in the soil collected after the last grass cutting, in each year of the study. Application of zinc to soil, regardless of its dose, resulted in a decrease in the activity of urease, dehydrogenase and alkaline phosphatase, although the significance of differences in relation to the control object was demonstrated only at higher doses, such as 400 and 600 mg Zn kg-1 soil. The study showed no negative effect of zinc on acid phosphatase activity. Organic fertilizers generally resulted in an increase in the enzymatic activity of the analyzed soil, and simultaneously limited the negative effects of higher zinc doses (400 and 600 mg Zn kg-1 of soil) on urease and dehydrogenase activity. During the consecutive years, urease and alkaline phosphatase activity decreased, while acid phosphatase activity increased. Dehydrogenase activity did not change significantly in the subsequent years of the study. [ABSTRACT FROM AUTHOR]

Membrane-bound quinoprotein glucose dehydrogenase from acetic acid bacteria produces lactobionic acid by the oxidation of lactose. Its enzymatic activity on lactose and maltose is much lower than that on D-glucose. For that reason, the activity of the enzyme on disaccharides has been considered low. In this study, we show that the isomaltose-oxidizing activity of acetic acid bacteria is much higher than their lactose-oxidizing activity. In addition to isomaltose, the enzyme oxidized gentiobiose and melibiose to the same extent. According to the characteristics of the isomaltose-oxidizing activity and investigations using dehydrogenase-deficient mutant bacteria, we identified the responsible enzyme as membrane-bound quinoprotein glucose dehydrogenase. Abbreviations: AAB: acetic acid bacteria; m-GDH: membrane-bound quinoprotein glucose dehydrogenase; DCIP: 2,6-dichlorophenolindophenol; DP: degree of polymerization; HPAEC-PAD: high-performance anion-exchange chromatography with pulsed amperometric detection; NMR: nuclear magnetic resonance; TLC: thin layer chromatography; COSY: correlation spectroscopy Membrane-bound quinoprotein glucose dehydrogenase (m-GDH) from acetic acid bacteria oxidizes disaccharides having α/β-1➝6 glycosidic linkages. [ABSTRACT FROM AUTHOR]

Abstract A Pseudomonas sp. DNE-S1 (GenBank accession number MF803832), able to degrade DEP in a wide range of acid-base conditions, was isolated from landfill soil. The growth kinetics of DNE-S1 on DEP followed the inhibition model. Fe3+ could promote the degradation ability of DNE-S1 to DEP probably by over-expression of the gene phthalate dihydrodiol dehydrogenase (ophB) and phthalate dioxygenase ferredoxin reductase (ophA4). The degradation rate of DEP (500 mg L−1 at 12 h) increased by 14.5% in the presence of Fe3+. Cu2+, Zn2+, and Mn2+ showed an inhibiting effect on the degradation performance of the strain and could alter the cellular morphology, surface area and volume of DNE-S1. Three degradation intermediates, namely ethyl methyl phthalate (EMP), dimethyl phthalate (DMP), and phthalic acid (PA), were detected in the biodegradation of DEP, and the biochemical pathway of DEP degradation was proposed. This study provides new information on the biochemical pathways and the responsible genes involved in DEP degradation. Highlights • Pseudomonas sp. DNE-S1 was able to degrade DEP in a wide range of acid-base conditions. • Two phthalate degrading genes ophB and ophA4 were identified in this bacterium. • Cellular morphology, surface area and volume were altered upon exposure to trace metal. • Fe3+ could promote the DEP degradation of DNE-S1. [ABSTRACT FROM AUTHOR]

Abstract Context Excessive adipose glucocorticoid action is associated with insulin resistance, but the mechanisms linking adipose glucocorticoid action to insulin resistance are still debated. We hypothesized that insulin resistance from excess glucocorticoid action may be attributed in part to increased ectopic lipid deposition in liver. Methods We tested this hypothesis in the adipose specific 11β-hydroxysteroid dehydrogenase-1 (HSD11B1) transgenic mouse, an established model of adipose glucocorticoid excess. Tissue specific insulin action was assessed by hyperinsulinemic-euglycemic clamps, hepatic lipid content was measured, hepatic insulin signaling was assessed by immunoblotting. The role of hepatic lipid content was further probed by administration of the functionally liver-targeted mitochondrial uncoupler, Controlled Release Mitochondrial Protonophore (CRMP). Findings High fat diet fed HSD11B1 transgenic mice developed more severe hepatic insulin resistance than littermate controls (endogenous suppression of hepatic glucose production was reduced by 3.8-fold, P < 0.05); this was reflected by decreased insulin-stimulated hepatic insulin receptor kinase tyrosine phosphorylation and AKT serine phosphorylation. Hepatic insulin resistance was associated with a 53% increase (P < 0.05) in hepatic triglyceride content, a 73% increase in diacylglycerol content (P < 0.01), and a 66% increase in PKCε translocation (P < 0.05). Hepatic insulin resistance was prevented with administration of CRMP by reversal of hepatic steatosis and prevention of hepatic diacylglycerol accumulation and PKCε activation. Conclusions These findings are consistent with excess adipose glucocorticoid activity being a predisposing factor for the development of lipid (diacylglycerol-PKCε)-induced hepatic insulin resistance. Highlights • Adipose glucocorticoid excess drives hepatic insulin resistance (IR) before obesity. • This IR is associated with hepatic steatosis; reversed by ectopic lipid depletion. • Hepatic IR is consistent with diacylglycerol-PKCε mediated IR. • More energy intake and reduced chylomicron clearance may explain hepatosteatosis. [ABSTRACT FROM AUTHOR]

Abstract Fusidic acid is the only fusidane-type antibiotic that has been clinically used. However, biosynthesis of this important molecule in fungi is poorly understood. We have recently elucidated the biosynthesis of fusidane-type antibiotic helvolic acid, which provides us with clues to identify a possible gene cluster for fusidic acid (fus cluster). This gene cluster consists of eight genes, among which six are conserved in the helvolic acid gene cluster except fusC1 and fusB1. Introduction of the two genes into the Aspergillus oryzae NSAR1 expressing the conserved six genes led to the production of fusidic acid. A stepwise introduction of fusC1 and fusB1 revealed that the two genes worked independently without a strict reaction order. Notably, we identified two short-chain dehydrogenase/reductase genes fusC1 and fusC2 in the fus cluster, which showed converse stereoselectivity in 3-ketoreduction. This is the first report on the biosynthesis and heterologous expression of fusidic acid. Graphical abstract Fusidane-type antibiotics, represented by fusidic acid, helvolic acid and cephalosporin P 1 , are a group of fungi-derived triterpenoid antibiotics. Here, we firstly identified the biosynthetic gene cluster of the clinically used fusidic acid and characterized its full biosynthetic pathway using a combinational biosynthetic approach. Notably, we identified two short-chain dehydrogenase/reductase FusC1 and FusC2 with converse stereoselectivity in 3-ketoreduction. fx1 [ABSTRACT FROM AUTHOR]

Graphical abstract ZnO NPs interact with cell systems and cellular organelles as intact particles as well as ions. Resultant induces inflammation mediated acute phase response that altered the iron homeostasis and promotes anemic condition. ZnO NPs – Zinc oxide nanoparticles, ROS-reactive oxygen species, APR- Acute phase response, Hep- hepcidin, Hp- haptoglobin, Heph- Hephaestin, FPN- ferroportin, TF- Transferrin receptor, TFR-1- Transferrin receptor-1, LDH- lactate dehydrogenase, Hb-hemoglobin, RBC- red blood cells. Highlights • Surface engineered ZnO nanoparticles (c-ZnO NPs) were synthesized & characterized. • Sub-acute oral toxicity of non functionalized b-ZnO and c-ZnO NPs were performed. • b-ZnO NPs induced higher inflammation that led to the acute phase response (APR). • APR leads to progression of anemia by altering interlinked iron signaling pathway. • Further, the surface modified c-ZnO NPs reduced the toxicity. Abstract Zinc oxide nanoparticles (ZnO NPs) are one of the most widely used nanomaterials. Following oral exposure, these NPs can accumulate in various organs and induce the toxicity due to their physiochemical characteristics. In present study to reduce the toxicity, surface engineered ZnO NPs (c-ZnO NPs) were in-situ synthesized by using polyacrylamide grafted guar gum (PAm-g-GG) polymer in alkaline media. Further, the comparative effect of bared ZnO NPs (b-ZnO NPs) and c-ZnO NPs were assessed on secondary target organ liver and kidneys of Swiss mice at doses of 10, 50 and 300 mg/kg following 28 days repeated oral treatment. The b-ZnO NPs were incited severe damages in liver and kidney tissue than c-ZnO NPs as seen by transmission electron microscopy and histopathology. The increased levels of serum biomarkers (AST, ALT, ALP, creatinine, uric acid, and urea) were also observed, that remarking a disturbance in the function of liver and kidney. After sub-acute oral treatment of b-ZnO NPs, the hepatic pro-inflammatory cytokines (IL-6, TNF-α, and MMP-9) were up-regulated that causes the activation of acute phase response (APR). We also observed significantly increased in expression of hepatic acute phase proteins (hepcidin and haptoglobin) and altered interlinked iron (Fe) signaling biomarkers (hephaestin, TF, TFR-1, LDH, and ferroportin). This study emphasizes that exposure to ZnO NPs may cause inflammation mediated APR through ultra-structural damage of tissue that could escort the progression of anemia. Nevertheless, the capping with PAm-g-GG in c- ZnO NPs has reduced the toxicity by altering the surface reactive property of ZnO NPs. [ABSTRACT FROM AUTHOR]

Plants, fungi, and some protists possess a more branched electron transport chain in their mitochondria compared to canonical one. In these organisms, the electron transport chain contains several rotenone-insensitive NAD(P)H dehydrogenases. Some are located on the outer surface, and others are located on the inner surface of the inner mitochondrial membrane. The putative role of these enzymes still remains elusive, but they may prevent the overreduction of the electron transport chain components and decrease the production of reaction oxygen species as a consequence. The last two decades resulted in the discovery of alternative rotenone-insensitive NAD(P)H dehydrogenases present in representatives of fungi and protozoa. The aim of this review is to gather and focus on current information concerning molecular and functional properties, regulation, and the physiological role of fungal and protozoan alternative NAD(P)H dehydrogenases. [ABSTRACT FROM AUTHOR]

Abstract A mechanistic interpretation of the kinetic profiles obtained for the stereoselective reduction of acetophenone promoted by Galactomyces candidus GZ1 under aerobic and anaerobic conditions was made. Based on experimental and bibliographical data, a mechanism which may involve the participation of two alcohol dehydrogenases with opposite stereoselectivities and alcohol oxidase is discussed. Due to the stereoselectivity of the reduction of acetophenone being changed when anaerobic conditions were used, this microorganism also permitted (S)-1-phenylethanol to be obtained in the absence of oxygen. Moreover, the kinetic profiles of the reactions of a racemic mixture of (R , S)-1-phenylethanol and pure (S)-1-phenylethanol with Gal. candidus were analyzed, which corroborated that there existed a reaction step where (S)-1-phenylethanol was oxidized to acetophenone. The results presented here show that not only is it possible to resolve racemic mixtures of phenylethanols when Gal. candidus is used as a biocatalyst, but that this is also efficient in causing the complete stereoinversion of pure (S)-1-phenylethanol to (R)-1-phenylethanol. Graphical abstract fx1 Highlights • Mechanism of the reduction of acetophenone catalyzed by Gal. candidus was studied. • Kinetic profile in aerobic and anaerobic conditions were obtained. • Anaerobic conditions invert the stereoselectivity of the reaction. • Participation of two alcohol dehydrogenase and an alcohol oxidase is discussed. • Due to the results obtained, other potential use of Gal. candidus were identified. [ABSTRACT FROM AUTHOR]

Highlights • Enzymatic CO 2 reduction with electrochemical NADH regeneration was studied. • Modified electrospun polystyrene nanofibers were used for FDH immobilization. • Electrochemical NADH regeneration supplied the enzymatic reaction properly. • The integrated process has a great potential for cofactor depended enzymatic reactions. Abstract Enzymatic conversion of CO 2 to formate was carried out in the cathodic cell of a two-chamber electrochemical apparatus where NAD+ was reduced on the surface of a Copper foam electrode. Formate dehydrogenase (FDH) was used as the biocatalyst in both free form and immobilized on the modified electrospun polystyrene nanofibers (EPSNF). The fabricated EPSNF were modified by a multistage procedure including acid treatment, silanization followed by activation with glutaraldehyde. The effects of regenerated NADH concentration and time of enzymatic reaction on the formate production in the both systems were studied. The results indicated that the EPSNF immobilized FDH had a desirable activity, long-term storage stability (41% after 20 days) and reusability after eight cycles of successive reactions (53% of the initial activity). Moreover, it was revealed that the increase of cofactor concentration at the early times of reaction was favorable to the formate production. However, an inhibitory effect was observed at higher concentrations of NADH, and the optimum values of 0.45 mM and 0.51 mM were obtained for the maximum enzyme activity by the free and immobilized enzymes respectively. The produced formate at the optimum cofactor concentration after 300 min was 0.61 mM and 0.31 mM for the free and immobilized enzyme systems. Finally, it can be concluded that the presented process is a promising approach to the enzymatic conversion of CO 2. [ABSTRACT FROM AUTHOR]

Summary Mutation of the isocitrate dehydrogenase 1 (IDH1) gene at codon 132 has been identified in approximately 70% of low-grade (II and III) human gliomas and secondary glioblastomas, with the IDH1 R132H point mutation representing 92.7% of these mutations. In people, the presence of an IDH1 gene mutation is associated with a better prognosis (both progression-free survival time and overall survival time) and a better response to therapy, including chemotherapy and radiation therapy. Furthermore, IDH1 mutations are included in diagnostic panels to improve diagnosis and molecular classification. Canine gliomas resemble their human counterpart both morphologically and immunohistochemically, therefore they are likely to share similar genetic abnormalities. The IDH1 gene is also comparable between man and dogs. If the IDH1 R132H point mutation is demonstrated in canine gliomas, the prognostic significance of this mutation in people may be transferable to the dog. The objective of this study was to investigate canine gliomas for the IDH1 R132H point mutation using immunohistochemistry. Thirty-one formalin-fixed and paraffin wax-embedded canine gliomas were examined for both IDH1 R132H expression and pan-IDH1 (IDH1 wild-type and point mutated IDH1). Glial tumour specimens were recorded to be either positive or negative for expression. Pan-IDH1 expression was identified in all 31 tumours (100%), while the IDH1 R132H point mutation was identified in none of the tumours (0%). Therefore, the IDH1 R132H point mutation was not identified in this population of canine gliomas and may not be a suitable biomarker or treatment target in canine gliomas. Further investigation is required to determine if other point mutations occur in the IDH1 gene of canine gliomas. [ABSTRACT FROM AUTHOR]

The biotransformation of citral, an industrially important monoterpenoid, has been extensively studied using many microbial biocatalysts. However, the metabolic pathways involved in its biotransformation are still unclear, because citral is a mixture of the trans-isomer geranial and the cis-isomer neral. Here, we applied the heterologous expression of geoA, a gene encoding geraniol dehydrogenase that specifically converts geraniol to geranial and nerol to neral, to identify the metabolic pathways involved in the biotransformation of citral. Acinetobacter sp. Tol 5 was employed in order to demonstrate the utility of this methodology. Tol 5 transformed citral to (1R,3R,4R)-1-methyl-4-(1-methylethenyl)-1,3-cyclohexanediol and geranic acid. Biotransformation of citral precursors (geraniol and nerol) by Tol 5 transformant cells expressing geoA revealed that these compounds were transformed specifically from geranial. Our methodology is expected to facilitate a better understanding of the metabolic pathways involved in the biotransformation of substrates that are unstable and include geometric isomers. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy (CH) is an important and independent predictor of morbidity and mortality. Through expression profiling, we recently identified a subset of genes (Dhrs7c, Decr, Dhrs11, Dhrs4, Hsd11b1, Hsd17b10, Hsd17b8, Blvrb, Pecr), all of which are members of the short‐chain dehydrogenase/reductase (SDR) superfamily and are highly expressed in the heart, that were significantly dysregulated in a rat model of CH caused by severe aortic valve regurgitation (AR). Here, we studied their expression in various models of CH, as well as factors influencing their regulation. Among the nine SDR genes studied, all but Hsd11b1 were down‐regulated in CH models (AR rats or mice infused with either isoproterenol or angiotensin II). This regulation showed a clear sex dimorphism, being more evident in males than in females irrespective of CH levels. In neonatal rat cardiomyocytes, we observed that treatment with the α1‐adrenergic receptor agonist phenylephrine mostly reproduced the observations made in CH animals models. Retinoic acid, on the other hand, stimulated the expression of most of the SDR genes studied, suggesting that their expression may be related to cardiomyocyte differentiation. Indeed, levels of expression were found to be higher in the hearts of adult animals than in neonatal cardiomyocytes. In conclusion, we identified a group of genes modulated in animal models of CH and mostly in males. This could be related to the activation of the fetal gene expression program in pathological CH situations, in which these highly expressed genes are down‐regulated in the adult heart. [ABSTRACT FROM AUTHOR]

Type 2 alternative NADH dehydrogenases (NDH‐2) participate indirectly in the generation of the electrochemical proton gradient by transferring electrons from NADH and NADPH into the ubiquinone pool. Due to their structural simplicity, alternative NADH dehydrogenases have been proposed as useful tools for gene therapy of cells with defects in the respiratory complex I. In this work, we report the presence of three open reading frames, which correspond to NDH‐2 genes in the genome of Ustilago maydis. These three genes were constitutively transcribed in cells cultured in YPD and minimal medium with glucose, ethanol, or lactate as carbon sources. Proteomic analysis showed that only two of the three NDH‐2 were associated with isolated mitochondria in all culture media. Oxygen consumption by permeabilized cells using NADH or NADPH was different for each condition, opening the possibility of posttranslational regulation. We confirmed the presence of both external and internal NADH dehydrogenases, as well as an external NADPH dehydrogenase insensitive to calcium. Higher oxygen consumption rates were observed during the exponential growth phase, suggesting that the activity of NADH and NADPH dehydrogenases is coupled to the dynamics of cell growth. [ABSTRACT FROM AUTHOR]

Carbon dioxide, CO 2 reduction and utilization for organic compounds synthesis are the potential technologies in environmental science and technology. In order to establish efficient CO 2 utilization technologies, an effective catalyst for CO 2 reduction and utilization is necessary. Among various catalysts, the biocatalyst is one of promising catalysts because it has excellent selectivity for the reaction and substrate. In this review, focusing on biocatalyst “formate dehydrogenase FDH” catalyzing CO 2 reduction to formic acid, representative examples of properties, types, structure of active-site of FDH and, reaction mechanism of formic acid oxidation and CO 2 reduction with FDH are outlined. A genetic engineering modified FDH and FDH immobilized various support for improving CO 2 reduction catalytic activity also are introduced. Moreover, chemical and electrochemical system of CO 2 reduction to formic acid with FDH, aqueous homogenous system of visible-light driven CO 2 reduction to formic acid with FDH and device for visible-light driven CO 2 reduction to formic acid with FDH are also introduced as an application of FDH. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of ammonia nitrogen loading rates and salinity levels on nutrients removal rates and substrate enzyme activities of constructed wetland (CW) microcosms planted with Salicornia bigelovii treating mariculture wastewater. Activities of urease (UA), dehydrogenase (DA), protease (PrA) and phosphatase (PA) were considered. Using principal component analysis (PCA), nutrient removal index (NRI) and enzyme activity index (EAI) were developed to evaluate the effects. The results revealed that increasing ammonia nitrogen loading rates had positive effects on nitrogen removal rates (i.e. NH 4 -N and DIN) and enhanced substrate enzyme activities. Compared with low salinity (i.e. 15 and 22), high salinity levels (i.e. 29 and 36) enhanced nutrients removal rates, DA and UA, but weaken PA and PrA. In conclusion, CW microcosms with Salicornia bigelovii can be used for the removal of nutrients under a range of ammonia nitrogen loadings and high salinity levels. [ABSTRACT FROM AUTHOR]

Branched-chain α-keto acid dehydrogenase (BCKDH) kinase (BDK) suppresses the branched-chain amino acid (BCAA) catabolism by inactivation of the BCKDH complex. The muscle-specific BDK-deficient (BDK-mKO) mice showed accelerated BCAA oxidation in muscle and decreased endurance capacity after training (Xu et al. PLoS One. 12 (2017) e0180989). We here report that BCAA supplementation overcompensated endurance capacity in BDK-mKO mice after training. [ABSTRACT FROM AUTHOR]

The increased use of antibiotics has raised concern regarding the environmental impacts of antibiotic residues in soil. In this study, we performed a laboratory experiment to compare the effect of two antibiotics: polymyxin B and penicillin G on the activity of alkaline phosphatase, acid phosphatase, dehydrogenases, and urease, in sandy loam and loamy sand. Antibiotics were applied to soil samples at the dosages: 2, 20, and 200 mg/kg DM. Soil without antibiotics was used as a control sample. The results showed that the contamination of soil with antibiotics affects the soil enzymes. Polymyxin B caused greater changes in enzyme activities than that of penicillin G. Moreover, greater changes in soil enzyme activities were observed in loamy sand than in sandy loam. Phosphatases were the most sensitive to the soil contamination with antibiotics. Principal component analysis showed that dehydrogenases were the most negatively correlated with PC1. [ABSTRACT FROM AUTHOR]

The increased use of antibiotics has raised concern regarding the environmental impacts of antibiotic residues in soil. In this study, we performed a laboratory experiment to compare the effect of two antibiotics: polymyxin B and penicillin G on the activity of alkaline phosphatase, acid phosphatase, dehydrogenases, and urease, in sandy loam and loamy sand. Antibiotics were applied to soil samples at the dosages: 2, 20, and 200 mg/kg DM. Soil without antibiotics was used as a control sample. The results showed that the contamination of soil with antibiotics affects the soil enzymes. Polymyxin B caused greater changes in enzyme activities than that of penicillin G. Moreover, greater changes in soil enzyme activities were observed in loamy sand than in sandy loam. Phosphatases were the most sensitive to the soil contamination with antibiotics. Principal component analysis showed that dehydrogenases were the most negatively correlated with PC1. [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether heat stress (HS) prevents a decrease in succinate dehydrogenase (SDH) activity and heat shock protein 60 (HSP60) and superoxide dismutase 2 (SOD2) contents in the extensor digitorum longus of streptozotocin (STZ)-induced diabetic rats. Twelve-week-old male Wistar rats were assigned to one of the four groups (n=6/group): control (Con), HS, diabetes mellitus (DM), and diabetes mellitus and heat stress (DM+HS). Diabetes was induced by the administration of STZ (50 mg/kg). HS was initiated 7 days after STZ treatment and performed at 42 °C for 30 min 5 times a week for 3 weeks. SDH activity was decreased in the DM and DM+HS groups. However, SDH activity was greater in the DM+HS group than in the DM group. Although HSP60 content was lower in the DM group than in the Con group, it was maintained in the DM+HS groups and was higher than that in the DM group. SOD2 content was decreased only in the DM group. These findings suggest that HS prevents the decrease in SDH activity in the skeletal muscle induced by DM. According to this mechanism, the maintenance of SOD2 and HSP60 by HS may suppress the increase in oxidative stress. [ABSTRACT FROM AUTHOR]

ThehypOgene fromSinorhizobium meliloti, located within thetrans-4-hydroxy-L-proline metabolic gene cluster, was first successfully expressed in the hostPseudomonas putida. Purified HypO protein functioned as a FAD-containingcis-4-hydroxy-D-proline dehydrogenase with a homomeric structure. In contrast to other known enzymes, significant activity for D-proline was found, confirming a previously proposed potential involvement in D-proline metabolism. [ABSTRACT FROM PUBLISHER]

Multifunctional enzyme, type-1 ( MFE1) is a monomeric enzyme with a 2E-enoyl-CoA hydratase and a 3S-hydroxyacyl-CoA dehydrogenase ( HAD) active site. Enzyme kinetic data of rat peroxisomal MFE1 show that the catalytic efficiencies for converting the short-chain substrate 2E-butenoyl-CoA into acetoacetyl-CoA are much lower when compared with those of the homologous monofunctional enzymes. The mode of binding of acetoacetyl-CoA (to the hydratase active site) and the very similar mode of binding of NAD+ and NADH (to the HAD part) are described and compared with those of their monofunctional counterparts. Structural comparisons suggest that the conformational flexibility of the HAD and hydratase parts of MFE1 are correlated. The possible importance of the conformational flexibility of MFE1 for its biocatalytic properties is discussed. Database Structural data are available in PDB database under the accession number . [ABSTRACT FROM AUTHOR]

InCorynebacterium glutamicum, the activity of the 2-oxoglutarate dehydrogenase (ODH) complex is negatively regulated by the unphosphorylated form of OdhI protein, which is critical for L-glutamate overproduction. We examined the potential impact of protein acylation at lysine (K)-132 of OdhI inC.glutamicumATCC13032. The K132E succinylation-mimic mutation reduced the ability of OdhI to bind OdhA, the catalytic subunit of the ODH complex, which reduced the inhibition of ODH activity.In vitrosuccinylation of OdhI protein also reduced the ability to inhibit ODH, and the K132R mutation blocked the effect. These results suggest that succinylation at K132 may attenuate the OdhI function. Consistent with these results, theC.glutamicummutant strain with OdhI-K132E showed decreased L-glutamate production. Our results indicated that not only phosphorylation but also succinylation of OdhI protein may regulate L-glutamate production inC.glutamicum. Succinylation at K132 of OdhI attenuates the OdhI function to inhibit ODH activity and affects L-glutamate production inCorynebacterium glutamicum. [ABSTRACT FROM AUTHOR]

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Objective To study the renal toxic effect of titanium dioxide nanoparticles (TiNPs) prepared by chemical and green route. Methods TiNPs were prepared by chemical (sol gel technique) and green route (using aqueous extract of Desmodium gangeticum root by using titanium tetraisopropoxide as precursor). Thus prepared TiNPs were characterized using UV–visible spectrophotometry, X-ray diffractometry and evaluated its renal toxic impact in different experimental models viz ., Wistar rats (100 mg/kg b.wt.; oral), LLC-PK1 cells (100 mg/mL) and isolated renal mitochondria (0.25, 0.5 and 1 mg/mL). Results Compared to the chemically synthesized TiNPs, Desmodium gangeticum synthesized nanoparticles showed less nephrotoxicity, determined by elevated serum renal markers like urea (62%), creatinine (35%), aspartate aminotransferase (61%) and alanine transaminase (37%) and the result was in agreement with cellular toxicity (measured by MTT assay and lactate dehydrogenase activity). Further toxicity evaluation at the level of mitochondria showed not much significant difference in TiNPs effect between two synthetic routes. Conclusions The biochemical findings in renal tissue and epithelial cell (LLC-PK1) supported by histopathology examination and isolated mitochondrial activity showed minor toxicity with TiNPs prepared by green route (TiNP DG) than TiNP Chem. [ABSTRACT FROM AUTHOR]

This review aims to give a detailed overview of various bioremediation technologies used for the decontamination of polychlorinated biphenyl (PCB)-polluted environments; discuss the bioaugmentation approaches employed to treat PCB-polluted soil, sediment, and wastewater; explore the limitations of bioaugmentation and the strategies to improve its efficiency; give an update on the current state of biodegradation studies on PCB and their mechanisms; explore the future research prospects on bioremediation based on the articles discussed in the current review. Extensive analysis of original works has revealed that the various bioremediation strategies displayed varying efficiencies with most found to be efficient. Coupling of treatment methods has been found effective in the decontamination of polluted sites. The biodegradation of PCB revealed that the concentrations of highly-chlorinated PCB can be substantially reduced under sequential anaerobic and aerobic processes. The study revealed that the concentrations of PCB in contaminated media declined largely due to the degradation of congeners with one or more chlorine atoms. Various enzymes participated in the degradation of PCB and include multicomponent dioxygenase (bphA, E, F, and G), dehydrogenases (bphB), second dioxygenase (bphC), and hydrolase (bphD). The review provides novel biological treatment strategies for the management of PCB-contaminated sites. [Display omitted] • Bioremediation technologies for PCB contaminated sites. • Coupling of treatment methods is effective in the decontamination of polluted sites. • VBNC cell resuscitation improves the degradation effectiveness of PCB. [ABSTRACT FROM AUTHOR]

The objective of the current study was to enzymatically characterize immobilized phytase as a glycoprotein on an optimal blend of starch/PAAm nanofibers. Aspergillus niger phytase (phyA) was first expressed in Hansenula polymorpha using formate dehydrogenase promoter and α-mating factor signal peptide. Response surface methodology was then used to optimize the different levels of the enzyme, temperature and pH on the immobilized phytase. The electrospun nanofibers showed uniform morphology with an average diameter of approximately 269 nm. Afterward, the kinetic parameters of Km (56 μM) and Vmax (401 μmol/min mg) of the immobilized enzyme improved, but the optimum pH and temperature had not changed in comparison with the soluble phytase. The applicability of the nanofiber was confirmed by its outstanding immobilization efficiency (193%) and suitable retention of catalytic activity of the immobilized phytase (50.4% after the tenth repetition). Optimal orientation of the enzyme on the nanofiber using the in silico approach was predicted, which could improve the kinetic properties. The results demonstrate the good potential of H. polymorpha as an efficient expression system for the production of glycoproteins for immobilization. [ABSTRACT FROM AUTHOR]

Visfatin is a multi-functional molecule that can act intracellularly and extracellularly as an adipokine, cytokine and enzyme. One of the main questions concerning visfatin is the mechanism of its secretion; whether, how and from which cells visfatin is released. The objective of this in vitro study was to observe the active secretion of visfatin from 3T3-L1 preadipocytes and adipocytes, HepG2 hepatocytes, U-937, THP-1 and HL-60 monocytes and macrophages. The amount of visfatin in media and cell lysate was always related to the intracellular enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), to exclude the passive release of visfatin. Visfatin was not found in media of 3T3-L1 preadipocytes. In media of 3T3-L1 adipocytes and HepG2 hepatocytes, the ratio of visfatin to the amount of GAPDH was identical to cell lysates. Hence, it is likely that these cells do not actively secrete visfatin in a significant manner. However, we found that significant producers of visfatin are differentiated macrophages and that the amount of secreted visfatin depends on used cell line and it is affected by the mode of differentiation. Results show that 3T3-L1 adipocytes and HepG2 hepatocytes released visfatin only passively during the cell death. U-937 macrophages secrete visfatin in the greatest level from all of the tested cell lines. [ABSTRACT FROM AUTHOR]

Ecdysone oxidase (EO) is an enzyme that catalyzes the oxidation of ecdysteroids, the molting steroid hormones in insects. This enzyme may play important roles in the conversion of ecdysteroids to 3-dehydroecdysteroids. In this study, we identified a novel EO, designated bmEO2, from the silkworm, Bombyx mori. A cDNA encoding bmEO2 was cloned by employing the reverse transcriptase-polymerase chain reaction (PCR) technique. The deduced amino acid sequence of bmEO2 showed conserved residues and sequence homology to other known insect EOs and glucose dehydrogenase proteins. Quantitative real-time PCR revealed that the bmEO2 transcript was abundantly present in larval testes of B. mori. [ABSTRACT FROM AUTHOR]

Objectives: Recent research demonstrates that lactate dehydrogenase (LDH) activity within the normal range may serve as a mediator in the (positive) relationship between physical activity and cardiovascular disease risk. Emerging work supports deleterious associations between sedentary behavior and health, independent of physical activity. Thus, this study evaluated if sedentary behavior was associated with normal-range LDH activity, independent of physical activity.Methods: Data from the 2003-2006 NHANES were used (N = 2,087 adults; 40-79 yrs). LDH activity levels were estimated from a blood sample using LX20 and LDH reagent; participants were included if they had LDH activity levels within the normal range (105-333 IU/L). Physical activity and sedentary behavior were assessed via accelerometry.Results: Sedentary behavior was inversely associated with normal-range LDH activity when physical activity was excluded from the model (OR = 0.89; 95% CI: 0.83-0.97, P = 0.009 for LDH activity quartile 4 vs. 1). However, sedentary behavior was no longer associated with normal-range LDH activity after controlling for physical activity and other covariates (OR = 1.00, P = 0.49 for LDH activity quartile 2 vs. 1; OR = 1.00, P = 0.72 for LDH quartile 3 vs. 1; and OR = 0.99, P = 0.36 for LDH quartile 4 vs. 1).Conclusion: Unlike physical activity, sedentary behavior is not independently associated with normal-range LDH activity. [ABSTRACT FROM AUTHOR]

Each cell types or tissues contain certain "physiological" levels of R-2-hydroxyglutarate (2HG), as well as enzymes for its synthesis and degradation. 2HG accumulates in certain tumors, possessing heterozygous point mutations of isocitrate dehydrogenases IDH1 (cytosolic) or IDH2 (mitochondrial) and contributes to strengthening their malignancy by inhibiting 2-oxoglutaratedependent dioxygenases. By blocking histone de-methylation and 5-methyl-cytosine hydroxylation, 2HG maintains cancer cells de-differentiated and promotes their proliferation. However, physiological 2HG formation and formation by non-mutant IDH1/2 in cancer cells were neglected. Consequently, low levels of 2HG might play certain physiological roles. We aimed to elucidate this issue and found that compared to highest 2HG levels in hepatocellular carcinoma HepG2 cells and moderate levels in neuroblastoma SH-SY5Y cells, rat primary fibroblast contained low basal 2HG levels at early passages. These levels increased at late passage and likewise 2HG/2OG ratios dropped without growth factors and enormously increased at hypoxia, reaching levels compared to cancer HepG2 cells. Responses in SH-SY5Y cells were opposite. Moreover, external 2HG supplementation enhanced fibroblast growth. Hence, we conclude that low 2HG levels facilitate cell proliferation in primary fibroblasts, acting via hypoxia-induced factor regulations and epigenetic changes. [ABSTRACT FROM AUTHOR]

Uneven ripening (UR) is a physiological disorder of unknown origin in ‘Bangalore blue’ grape (Vitis vinifera×Vitis labrusca) leading to wine of inferior quality. A preliminary study found wide variations in total dehydrogenase activity (TDH) of seeds from unevenly ripe berries. In our experiments, gibberellin (GA3) applied to young grapes increased seed TDH activity and reduced the incidence of uneven ripening to 2% compared with 35% in the control. In contrast, paclobutrazol (PBZ) decreased TDH activity and increased the incidence of the disorder to 58%. GA3-treated berries had higher concentrations of sucrose and TDH activity in seed representing mature seeds with high viability. In contrast, PBZ-treated and control berries had higher concentrations of glucose and lower TDH activity, indicating immature seeds with low viability. These results suggested that competition among developing berries can lead to differences in seed gibberellin content, seed viability and the rate of berry growth resulting in green, purple, and black berries at harvest. The study established the role of seed viability in uneven ripening and demonstrated that the incidence of the disorder is reduced by the application of GA3to immature berries. [ABSTRACT FROM PUBLISHER]

Aim: The propagation of S. aureus in hospital and dental environments is considered an important public health problem since resistant strains can cause serious infections in humans. The genetic variability of 99 oxacillin-resistant S. aureus isolates (ORSA) from the dental patients (oral cavity) and environments (air) was studied by isoenzyme genotyping. Methods: S. aureus isolates were studied using isoenzyme markers (alcohol dehydrogenase, sorbitol dehydrogenase, mannitol-1-phosphate dehydrogenase, malate dehydrogenase, glucose dehydrogenase, D-galactose dehydrogenase, glucose-6-phosphate dehydrogenase, catalase and α/β-esterase) and genetic (Nei's statistics) and cluster analysis (UPGMA algorithm). Results: A highly frequent polyclonal pattern was observed in this population of ORSA isolates, suggesting various sources of contamination or microbial dispersion. Genetic relationship analysis showed a high degree of polymorphism between the strains, and it revealed three taxa (A, B and C) distantly genetically related (0.653≤dij≤1.432) and fifteen clusters (I to XV) moderately related (0.282≤dij<0.653). These clusters harbored two or more highly related strains (0≤dij<0.282), and the existence of microevolutionary processes in the population of ORSA. Conclusion: This research reinforces the hypothesis of the existence of several sources of contamination and/or dispersal of ORSA of clinical and epidemiologically importance, which could be associated with carriers (patients) and dental environmental (air). [ABSTRACT FROM AUTHOR]

Elevated concentrations of heavy metals and antibiotics often coexist in agricultural soils due to land application of large amounts of animal manure. The experiment was conducted to investigate the single and joint effects of different concentrations of sulfadiazine (SDZ) (10 mg kg −1 and 100 mg kg −1 ) and copper (Cu) (20 mg kg −1 and 200 mg kg −1 ) on soil microbial activity, i.e. fluorescein diacetate (FDA) hydrolysis, dehydrogenase (DHA) and basal respiration (BR), microbial biomass and community structure estimated using phospholipid fatty acids (PLFA), and community level physiological profiles (CLPP) using MicroResp™. High concentration of SDZ or Cu significantly reduced microbial activity during the whole incubation period, while the inhibiting effect of low concentration of SDZ or Cu was only visible within 14 days of incubation. The total PLFA concentration was reduced by SDZ and/or Cu, which resulted from reduced bacterial and actinomycetic biomass. The addition of SDZ and/or Cu decreased the bacteria:fungi ratio, whereas only the addition of high Cu concentration significantly decreased Gram + :Gram − ratio. The addition of Cu obviously inhibited the dissipation of SDZ, which could affect the combined effects of both on microbial activity, biomass and community structure. Principal component analysis of the CLPP and PLFA data clearly revealed the notable effects of SDZ and/or Cu on soil microbial community structure. [ABSTRACT FROM AUTHOR]

Raillietina species are prevalent in domestic chickens (Gallus gallus domesticus) in Phayao province, northern Thailand. Their infection may cause disease and death, which affects the public health and economic situation in chicken farms. The identification of Raillietina has been based on morphology and molecular analysis. In this study, morphological observations using light (LM) and scanning electron microscopies (SEM) coupled with molecular analysis of the internal transcribed spacer 2 (ITS2) region and the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene were employed for precise identification and phylogenetic relationship studies of Raillietina spp. Four Raillietina species, including R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp., were recovered in domestic chickens from 4 districts in Phayao province, Thailand. LM and SEM observations revealed differences in the morphology of the scolex, position of the genital pore, number of eggs per egg capsule, and rostellar opening surface structures in all 4 species. Phylogenetic relationships were found among the phylogenetic trees obtained by the maximum likelihood and distance-based neighbor- joining methods. ITS2 and ND1 sequence data recorded from Raillietina sp. appeared to be monophyletic. The query sequences of R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp. were separated according to the different morphological characters. This study confirmed that morphological studies combined with molecular analyses can differentiate related species within the genus Raillietina in Thailand. [ABSTRACT FROM AUTHOR]

The presence of selected dehydrogenases, including alcohol dehydrogenase (ADH-YL) and aldehyde dehydrogenase (ALDH-YL), inYarrowia lipolyticaJMY 861, and their potential role in flavor synthesis were investigated. The experimental findings showed that using reduced form of nicotinamide adenine dinucleotide (NADH) as cofactor, the ADH-YL activityin vitrowas 6-fold higher than that with reduced form of nicotinamide adenine dinucleotide phosphate (NADPH); however, under the experimental conditions used in this study, an ALDH-YL activity was not detected. Thein situhexanal reduction reaction was found to be instantaneous; however, when the yeast cells suspension was diluted 150 times, the initial relative hexanal concentration was increased by 84.1%. The chromatographic analyses indicated the conversion,in situ, of linoleic acid hydroperoxides (HPODs) into volatile C6-compounds after 60 min of HPODs addition to the yeast cells suspension. An endogenous alcohol dehydrogenase inYarrowia lipolyticaJMY 861 along with the genetically cloned hydroperoxide lyase from green bell pepper. [ABSTRACT FROM PUBLISHER]

Cytokinin oxidase/dehydrogenases (CKXs) in plants are coded by a small multigene family and play important roles in maintaining cytokinin homeostasis. In this study, fourCKXgenes (i.e.PsCKX1, PsCKX2, PsCKX5, andPsCKX7) were cloned fromPoncirus trifoliata. All PsCKXs contained a highly conserved flavin adenine dinucleotide (FAD) binding domain and a cytokinin dehydrogenase 1, FAD/cytokinin binding domain. PsCKX1 and PsCKX2 shared 66.2% and 65.4% identity with AtCKX6 and AtCKX1, respectively, while PsCKX5 and PsCKX7 exhibited less than 45% identity with AtCKXs. The expression analysis under abiotic conditions (NaCl, ABA, 6-BA and drought) revealed that the fourPsCKXgenes could respond to at least one treatment, and the expression patterns were diverse in root and leaf. Overexpressing fourPsCKXgenes in tobacco led to diverse phenotypic variations in transgenic plant, including leaf shape, root architecture, and plant height. In addition, the data showed thatPsCKX2andPsCKX5hold promise to obtain citrus dwarf rootstock with a stronger root system, since the overexpression of them resulted in dwarf plants with more lateral roots. Taken together, the work lays the basis for applications ofPsCKXgenes in future. [ABSTRACT FROM PUBLISHER]

A bacterial consortium was selected in the presence of Cu from sediment samples taken from Sepetiba Bay, Brazil, which is a site historically contaminated by metals. Bacteria were exposed to 0, 1, 6, 12.5, 25 and 50 μg·mL − 1 Cu, Pb and Cu + Pb for 11 days of bioassay. Results showed Alcanivorax dominance (81%) and cell counts of 10 8 cells·mL − 1 . However, a reduction in dehydrogenase activity was observed from the fifth day of exposure for all Cu, Pb, and Cu + Pb concentrations tested. Esterase activity tended to increase, indicating higher energy demand to complete the bacterial lifecycle. Pb concentrations in the filtered culture medium (0.2 μm) were below the detection limit, indicating biosorption, whereas concentrations of Cu were close to the tested concentrations, indicative of efflux. Results suggest the need for biomarkers, such as esterase and dehydrogenase enzymatic activity, in the assessment of resistance and tolerance of communities previously exposed to stressors. [ABSTRACT FROM AUTHOR]