Reductase Protein Research Articles

Synthesis, experimental antimicrobial activity, theoretical vibrational analysis, quantum chemical modeling and molecular docking studies of (E)-4-(benzylideneamino)benzenesulfonamide

(E)-4-(benzylideneamino)benzenesulfonamide (M1) compound was synthesized with a reaction of benzaldehyde and sulfanilamide; the resulting compound was confirmed with characterization studies like Infrared, UV-Visible, 1HNMR, and 13CNMR. M1 compound compared with theoretical study consuming DFT with support of Gaussian 09 software package. The Infrared was done by DFT way with B3LYP/631G+(d,p) and B3LYP/6311G+(d,p) basis set. The physical properties (ADMET) show an excellent bioactivity score which is 0.55 were done by the Swiss ADME online tool. The MD lessons were done by Auto-dock; it shows the highest binding energy is -7.66 interacted with Human carbonyl reductase (4Z3D) protein. Discovery Studio is used for protein preparation and result visualization. Wave functions like ELF, LOL, ALIE, and RDG show excellent results calculated from Multiwfn software. Antimicrobial activity studies indicate the compound has high antibacterial activity compared to Clindamycin (positive control).

Iodate Reduction by Shewanella oneidensis Requires Genes Encoding an Extracellular Dimethylsulfoxide Reductase.

Microbial iodate (IO3–) reduction is a major component of the iodine biogeochemical reaction network in anaerobic marine basins and radioactive iodine-contaminated subsurface environments. Alternative iodine remediation technologies include microbial reduction of IO3– to iodide (I–) and microbial methylation of I– to volatile gases. The metal reduction pathway is required for anaerobic IO3– respiration by the gammaproteobacterium Shewanella oneidensis. However, the terminal IO3– reductase and additional enzymes involved in the S. oneidensis IO3– electron transport chain have not yet been identified. In this study, gene deletion mutants deficient in four extracellular electron conduits (EECs; ΔmtrA, ΔmtrA-ΔmtrDEF, ΔmtrA-ΔdmsEF, ΔmtrA-ΔSO4360) and DMSO reductase (ΔdmsB) of S. oneidensis were constructed and examined for anaerobic IO3– reduction activity with either 20 mM lactate or formate as an electron donor. IO3– reduction rate experiments were conducted under anaerobic conditions in defined minimal medium amended with 250 μM IO3– as anaerobic electron acceptor. Only the ΔmtrA mutant displayed a severe deficiency in IO3– reduction activity with lactate as the electron donor, which suggested that the EEC-associated decaheme cytochrome was required for lactate-dependent IO3– reduction. The ΔmtrA-ΔdmsEF triple mutant displayed a severe deficiency in IO3– reduction activity with formate as the electron donor, whereas ΔmtrA-ΔmtrDEF and ΔmtrA-ΔSO4360 retained moderate IO3– reduction activity, which suggested that the EEC-associated dimethylsulfoxide (DMSO) reductase membrane-spanning protein DmsE, but not MtrA, was required for formate-dependent IO3– reduction. Furthermore, gene deletion mutant ΔdmsB (deficient in the extracellular terminal DMSO reductase protein DmsB) and wild-type cells grown with tungsten replacing molybdenum (a required co-factor for DmsA catalytic activity) in defined growth medium were unable to reduce IO3– with either lactate or formate as the electron donor, which indicated that the DmsAB complex functions as an extracellular IO3– terminal reductase for both electron donors. Results of this study provide complementary genetic and phenotypic evidence that the extracellular DMSO reductase complex DmsAB of S. oneidensis displays broad substrate specificity and reduces IO3– as an alternate terminal electron acceptor.

Enhancement effects of dissolved organic matter leached from sewage sludge on microbial reduction and immobilization of Cr(VI) by Geobacter sulfurreducens

Sewage sludge has a high concentration of dissolved organic matter (DOM) which contains compounds that can serve as electron donors or shuttles for metal reduction by dissimilatory metal reducing bacteria (DMRB). In this study, Cr(VI) removal by G. sulfurreducens, a common DMRB present in anaerobic soils, was examined in the presence or absence of sludge DOM. Two different types of sludge DOM were tested; composted sludge DOM (C-DOM) and anaerobically digested sludge DOM (A-DOM). Both sludge DOMs enhanced Cr(VI) reduction by G. sulfurreducens, but C-DOM was more effective likely because it had higher concentrations of humic substances that served as electron shuttles. Transcriptomic studies indicated that G. sulfurreducens utilizes several different mechanisms to tolerate chromium including extracellular Cr(VI) reduction and immobilization by outer membrane c-type cytochromes and electrically conductive pili, intracellular Cr(VI) reduction by triheme cytochromes and NAD(P)H FMN reductase proteins, and chromium efflux by several P-type ATPase and RND transporter proteins. Microscopy experiments also showed that Cr(III) crystals formed on the surface of the cells, indicating that extracellular Cr(VI) reduction and adsorption was involved in the chromium removal process. These results help provide insight into the potential use of sewage sludge as an additive to enhance the bioremediation of chromium contaminated soils.

Genome-Wide Identification and Expression Analysis of the Thioredoxin (Trx) Gene Family Reveals Its Role in Leaf Rust Resistance in Wheat (Triticum aestivum L.).

Bread wheat (Triticum aestivum L.; Ta) is the staple cereal crop for the majority of the world’s population. Leaf rust disease caused by the obligate fungal pathogen, Puccinia triticina L., is a biotrophic pathogen causing significant economic yield damage. The alteration in the redox homeostasis of the cell caused by various kinds of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in response to pathogenic infections is controlled by redox regulators. Thioredoxin (Trx) is one of the redox regulators with low molecular weight and is thermostable. Through a genome-wide approach, forty-two (42) wheat Trx genes (TaTrx) were identified across the wheat chromosome groups A, B, and D genomes containing 12, 16, and 14 Trx genes, respectively. Based on in silico expression analysis, 15 TaTrx genes were selected and utilized for further experimentation. These 15 genes were clustered into six groups by phylogenetic analysis. MicroRNA (miRNA) target analysis revealed eight different miRNA-targeted TaTrx genes. Protein–protein interaction (PPI) analysis showed TaTrx proteins interact with thioredoxin reductase, peroxiredoxin, and uncharacterized proteins. Expression profiles resulting from quantitative real-time PCR (qRT-PCR) revealed four TaTrx genes (TaTrx11-5A, TaTrx13-5B, TaTrx14-5D, and TaTrx15-3B) were significantly induced in response to leaf rust infection. Localization of ROS and its content estimation and an assay of antioxidant enzymes and expression analysis suggested that Trx have been involved in ROS homeostasis at span 24HAI-72HAI during the leaf rust resistance.

Rational Optimization of Dihydropyrimidinone-Quinoline Hybrids as Plasmodium falciparum Glutathione Reductase Inhibitors.

A series of dihydropyrimidinone-based antimalarial compounds were designed and synthesised based on the previously identified amide-based quinoline hybrids which showed good resistance reversal ability against the resistant strain of Plasmodium falciparum. The aromatic ring on the dihydropyrimidinone of the original hits was exchanged for a methyl group to bring the molecular weights below 500 Da and also determine the effect of the aromatic ring count on the resistance reversal ability of the hybrids. Apart from the previously used amide bond, the hybrid linker was also extended to the triazole linker. Although the triazole linker is synthetically easier to access, the use of an amide linker seems to have an activity advantage. The synthesised compounds in addition to the previously identified hits were subjected to molecular docking particularly targeting the orthosteric site of Plasmodium falciparum glutathione reductase (PfGR) protein. The ligand with the best binding interaction was rationally optimised to increase its suitability as a competitive inhibitor against the cofactor of the PfGR. Two of the optimised ligands showed better binding affinities than the cofactor while one of the two ligands displayed hydrophobically packed correlated hydrogen-bond which is very important in maintaining the ligand stability within the protein. In silico ADME predictions of the synthesised compounds indicate that these compounds possess good pharmacokinetic properties.

Front Cover: Gallium (III) Complexes in Cancer Chemotherapy (Eur. J. Inorg. Chem. 6/2022)

The Front Cover shows the major antineoplastic mechanisms of gallium compounds. Gallium, whose name originates from the Latin word “Gallus (the Rooster)”, has been considered as one of the main-group elements potentially used in chemotherapy for decades. Gallium compounds, such as Ga(NO3)3, inhibit tumors by relying on the similarity between Ga3+ and Fe3+, the latter of which plays a crucial role in enzyme catalysis and redox homeostasis. Ga3+ ions enter the cells through transferrin-mediated endocytosis and are released after acidification of endosomes. Later on, they interrupt Fe-dependent processes; for example, they inhibit the activity of ribonucleotide reductase (leading to cell cycle arrest) and Fe-containing proteins in the respiratory chain (leading to the generation of ROS). To solve the problem of complex Ga(III) speciation in the circulatory system, a large number of ligands were applied to form Ga(III) complexes, supplying multiple theranostic functions and novel modes of action. More information can be found in the Review by J.-L. Zhang and co-workers.

Isoniazid: An Exploratory Review

Isoniazid (INH) is one of the most successful tuberculosis medications in the market today. In particular, isoniazid is used as a prophylaxis medication to avoid resurgence of illness in those who have underlying Mycobacterium tuberculosis (MTB) infection. The mode of action of isoniazid is complicated and incorporates a number of distinct aspects in which various biomolecular routes are impacted, including mycolic acid production. Catalase-peroxidase (KatG) activates the prodrug isoniazid and enzymes such as β-ketoacyl ACP synthase (KasA) and enoyl acyl carrier protein (ACP) reductase target the active isoniazid products. Various genes in diverse biochemical networks and pathways are involved in the physiological mechanisms of isoniazid resistance. Isoniazid resistance is the most common of all clinical drug-resistant isolates, with incidence in some areas of up to 20 to 30%. In this review article, several existing components that may influence to the complexities of isoniazid function including mechanism of action, resistance mechanisms in MTB, along with their history, different synthetic procedures, uses, dosage forms, side effects, adverse drug reactions, physico-chemical characteristics, ADME properties, contraindications as well as future perspectives are discussed. Studies of pharmacokinetics have found that the cause of the drug mediated hepatotoxicity is possible by metabolism of isoniazid. Because of inter-individual heterogeneity of polymorphism that affect isoniazid metabolism rates, customized medicines may be required in various populations to prevent hepatotoxicity. The isoniazid multidrug combination treatment which would proved to be effective tuberculosis treatment in future. Further exploration is needed for better comprehension of pathogenesis mechanism of Mycobacterium tuberculosis (MTB) and drug resistance studies are required for building up better therapeutics and diagnostic against tuberculosis.

Ethanol and Acetic Acid Induces Conformational Changes in Zebrafish Dihydrofolate Reductase Protein

An equilibrium unfolding research of the recombinant zDHFR would provide information on the conformational changes of protein. In present work, the conformation of recombinant zDHFR was investigated in presence of ethanol and acetic acid. Equilibrium unfolding of recombinant zDHFR was monitored by enzymatic assay after denaturation by ethanol and acetic acid at 340 nm. Changes in secondary and tertiary structure of zDHFR with increasing ethanol and acetic acid concentrations were investigated in far-UV circular dichroism (CD) (190 to 250 nm) and fluorescence spectroscopy (emission spectra from 300 to 400 nm with an excitation wavelength of 295 nm) methods. It has been observed that in case of acetic acid-induced denaturation of zDHFR, the shift from native to denatured state occurs in a single step, whereas intermediates or non-native states are found at low concentrations of ethanol. The recent findings have significant implications for understanding how ethanol and acetic acid affect protein structure.

ACTIVE COMPOUNDS PREDICTION OF CABE JAMU (PIPER RETROFRACTUM) AS ANTI DIABETIC AGENT

Diabetes mellitus is a metabolic disorder disease which is the fourth leading cause of death in Indonesia. The number of people with diabetes in Indonesia shows an increase from year to year, in 2007 people with diabetes reached 14.7% of the population and it is predicted that in 2030 the number of people with diabetes in Indonesia will reach 21.3 million people. Globally, Indonesia ranks fourth in the number of diabetics after India, China and the United States. Herbal medicines from spices have the opportunity to be developed into antidiabetic agents, with considerations of safety, minimal side effects and cheap. Several types of spices have been reported to be used as antidiabetic agents. Cabe jamu, one of the famous spices in Madura, has been reported to have many health benefits. This study will identify the active compounds in cabe jamu that have the ability as antidiabetics by using a molecular docking approach. The results of the study found that cabe jamu has 22 active compounds that have the potential as herbal medicines. Of the 22 active compounds, 10 of them were successfully docked with diabetes aldose reductase protein. The results of this study indicate that the active compounds contained in cabe jamu have the ability as an antidiabetic agent. Based on the strength of the hidrogen bond, and the absence of toxic potential, 3 active compounds from cabe jamu that have strong antidiabetic abilities and no toxic potential were obtained, namely piperine, retrofractamide C, and guineensine.

Proteomic analysis reveals different responses to drought between the Cleome spinosa (C3) and Cleome gynandra (C4)

The global emergence of low water availability causes extensive damage to crops in many regions. Although the responses of plants to drought stress have been extensively investigated, molecular studies on plants with different carboxylation pathways are limited. Therefore, we aimed to identify quantitative differences in proteins functioning in differential drought tolerance of C3 (Cleome spinosa) and C4 (C. gynandra) species. Proteomic analysis functionally characterized 33 differentially accumulated proteins in C. spinosa and 15 proteins in C. gynandra leaves. The identified proteins were involved in multiple aspects of leaf metabolism such as photosynthesis, energy metabolism, protein metabolism, and stress defense. The up-regulated accumulation of RuBisCO proteins may have contributed to carboxylation in stressed C. spinosa, but RuBisCO activase proteins were severely down-regulated. Additionally, down-regulation of ferredoxin-nicotinamide adenine dinucleotide phosphate (NADP) reductase and oxygen-evolving enhancer proteins was only found in C. spinosa, which possibly related to the inhibition of electron flow. The up-regulation of enolase may contribute to the energy requirement in C. gynandra, while down-regulation of glycolytic enzymes, such as fructose-bisphosphate aldolase and triosephosphate isomerase, was found in C. spinosa suggesting the impaired energy metabolism under drought stress. The proteomic analysis suggests different adaptive strategies between C. spinosa and C. gynandra against drought stress.

Quantitative Proteome Profiling of a S-Nitrosoglutathione Reductase (GSNOR) Null Mutant Reveals a New Class of Enzymes Involved in Nitric Oxide Homeostasis in Plants.

Nitric oxide (NO) is a short-lived radical gas that acts as a signaling molecule in all higher organisms, and that is involved in multiple plant processes, including germination, root growth, and fertility. Regulation of NO-levels is predominantly achieved by reaction of oxidation products of NO with glutathione to form S-nitrosoglutathione (GSNO), the principal bioactive form of NO. The enzyme S-nitrosoglutathione reductase (GSNOR) is a major route of NADH-dependent GSNO catabolism and is critical to NO homeostasis. Here, we performed a proteomic analysis examining changes in the total leaf proteome of an Arabidopsis thaliana GSNOR null mutant (hot5-2/gsnor1-3). Significant increases or decreases in proteins associated with chlorophyll metabolism and with redox and stress metabolism provide insight into phenotypes observed in hot5-2/gsnor1-3 plants. Importantly, we identified a significant increase in proteins that belong to the aldo-keto reductase (AKR) protein superfamily, AKR4C8 and 9. Because specific AKRs have been linked to NO metabolism in mammals, we expressed and purified A. thaliana AKR4C8 and 9 and close homologs AKR4C10 and 11 and determined that they have NADPH-dependent activity in GSNO and S-nitroso-coenzyme A (SNO-CoA) reduction. Further, we found an increase of NADPH-dependent GSNO reduction activity in hot5-2/gsnor1-3 mutant plants. These data uncover a new, NADPH-dependent component of NO metabolism that may be integrated with NADH-dependent GSNOR activity to control NO homeostasis in plants.

Anti-Methanogenic Effect of Phytochemicals on Methyl-Coenzyme M Reductase—Potential: In Silico and Molecular Docking Studies for Environmental Protection

Methane is a greenhouse gas which poses a great threat to life on earth as its emissions directly contribute to global warming and methane has a 28-fold higher warming potential over that of carbon dioxide. Ruminants have been identified as a major source of methane emission as a result of methanogenesis by their respective gut microbiomes. Various plants produce highly bioactive compounds which can be investigated to find a potential inhibitor of methyl-coenzyme M reductase (the target protein for methanogenesis). To speed up the process and to limit the use of laboratory resources, the present study uses an in-silico molecular docking approach to explore the anti-methanogenic properties of phytochemicals from Cymbopogon citratus, Origanum vulgare, Lavandula officinalis, Cinnamomum zeylanicum, Piper betle, Cuminum cyminum, Ocimum gratissimum, Salvia sclarea, Allium sativum, Rosmarinus officinalis and Thymus vulgaris. A total of 168 compounds from 11 plants were virtually screened. Finally, 25 scrutinized compounds were evaluated against methyl-coenzyme M reductase (MCR) protein using the AutoDock 4.0 program. In conclusion, the study identified 21 out of 25 compounds against inhibition of the MCR protein. Particularly, five compounds: rosmarinic acid (−10.71 kcal/mol), biotin (−9.38 kcal/mol), α-cadinol (−8.16 kcal/mol), (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one (−12.21 kcal/mol), and 2,4,7,9-tetramethyl-5decyn4,7diol (−9.02 kcal/mol) showed higher binding energy towards the MCR protein. In turn, these compounds have potential utility as rumen methanogenic inhibitors in the proposed methane inhibitor program. Ultimately, molecular dynamics simulations of rosmarinic acid and (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one yielded the best possible interaction and stability with the active site of 5A8K protein for 20 ns.

Altered vitamin K biodistribution and metabolism in experimental and human chronic kidney disease

Chronic kidney disease (CKD) is accompanied with extensive cardiovascular calcification, in part correlating with functional vitamin K deficiency. Here, we sought to determine causes for vitamin K deficiency beyond reduced dietary intake. Initially, vitamin K uptake and distribution into circulating lipoproteins after a single administration of vitamin K1 plus K2 (menaquinone 4 and menaquinone 7, respectively) was determined in patients on dialysis therapy and healthy individuals. The patients incorporated very little menaquinone 7 but more menaquinone 4 into high density lipoprotein (HDL) and low-density lipoprotein particles than did healthy individuals. In contrast to healthy persons, HDL particles from the patients could not be spiked with menaquinone 7 invitro and HDL uptake was diminished in osteoblasts. A reduced carboxylation activity (low vitamin K activity) of uremic HDL particles spiked with menaquinone 7 vs. that of controls was confirmed in a bioassay using human primary vascular smooth muscle cells. Kidney menaquinone 4 tissue levels were reduced in 5/6-nephrectomized versus sham-operated C57BL/6 mice after four weeks of a vitamin K rich diet. From the analyzed enzymes involved in vitamin K metabolism, kidney HMG-CoA reductase protein was reduced in both rats and patients with CKD. In a trial on the efficacy and safety of atorvastatin in 1051 patients with type 2 diabetes receiving dialysis therapy, no pronounced vitamin K deficiency was noted. However, the highest levels of PIVKA-II (biomarker of subclinical vitamin K deficiency) were noted when a statin was combined with a proton pump inhibitor. Thus, profound disturbances in lipoprotein mediated vitamin K transport and metabolism in uremia suggest that menaquinone 7 supplementation to patients on dialysis therapy has reduced efficacy.

YgfY Contributes to Stress Tolerance in Shewanella oneidensis Neither as an Antitoxin Nor as a Flavinylation Factor of Succinate Dehydrogenase.

YgfY(SdhE/CptB) is highly conserved while has controversial functions in bacteria. It works as an antitoxin and composes a type IV toxin–antitoxin system with YgfX(CptA) typically in Escherichia coli, while functions as an flavinylation factor of succinate dehydrogenase and fumarate reductase typically in Serratia sp. In this study, we report the contribution of YgfY in Shewanella oneidensis MR-1 to tolerance of low temperature and nitrite. YgfY deficiency causes several growth defects of S. oneidensis MR-1 at low temperature, while YgfX do not cause a growth defect or morphological change of S. oneidensis MR1-1 and E. coli. YgfY do not interact with FtsZ and MreB nor with YgfX examined by bacterial two-hybrid assay. YgfY effect on growth under low temperature is not attributed to succinate dehydrogenase (SDH) because a mutant without SDH grows comparably with the wild-type strain in the presence of succinate. The ygfY mutant shows impaired tolerance to nitrite. Transcription of nitrite reductase and most ribosome proteins is significantly decreased in the ygfY mutant, which is consistent with the phenotypes detected above. Effects of YgfY on growth and nitrite tolerance are closely related to the RGXXE motif in YgfY. In summary, this study demonstrates pleiotropic impacts of YgfY in S. oneidensis MR-1, and sheds a light on the physiological versatility of YgfY in bacteria.

Construction of 3D Model of Protein Drug Targets for Renibacterium Salmoninarum - A Bacterial Pathogen Causing Bacterial Kidney Disease in Young Salmonid Fish

The aim of this study is to construct 3D models of potential drug targets for the Bacterial Kidney Disease (BKD) causing pathogen Renibacterium salmoninarum. The bacterial pathogen Renibacterium salmoninarum was selected for homology modeling studies since there were no known protein structures of the organism reported in the NCBI database. The reported protein sequences were run through DrugBank to pick out drug-targets. Online databases and web tools such as PMDB, UniProt, Drug Bank, and SwissModel were employed in this analysis. An aggregate of 412 protein sequences were identified as potential drug targets and were retrieved from the UniProt. Homology models of the protein sequences were constructed using the SwissModel database for all 412 proteins. These were then refined through a protein blast and Ramachandran plot analysis. Out of the 412 constructed models, 143 models were of reliable quality. These were then submitted to the PMDB database for further reference. To demonstrate the application of these constructed models, protein-ligand docking analysis using Auto Dock Vina was performed. Among the antibiotics that were tested against their known drug targets, trimethoprim demonstrated significant potential for the inhibition of R. salmoninarum’s dihydrofolate reductase protein, with a binding energy of -9.06 Kcal/mol and with the formation of 3 hydrogen bonds. Therefore through protein-ligand docking studies and the construction of 3D models of protein drug targets, Trimethoprim is proposed as a solution to the Bacterial Kidney Disease (BKD) problem in salmonid fishes. Further in-vitro evidences are in demand to prove this hypothesis.

Ribonucleotide reductase: In-vitro S-glutathionylation of R2 and p53R2 subunits of mammalian class I ribonucleotide reductase protein.

Ribonucleotide reductases (RNR) catalyze the rate-limiting step in DNA synthesis during the S-phase of the cell cycle. Its constant activity in order to maintain dNTP homeostasis is a fascinating area of research and an attractive candidate for cancer research and antiviral drugs. Redox modification such as S-glutathionylation of the R1 subunit of mammalian RNR protein has been presumed to regulate the activity of RNR during catalytic cycles. Herein, we report S-glutathionylation of the R2 subunit. We have also shown Grx1 system can efficiently deglutathionylate the S-glutathionylated R2 subunit. Additionally, our data also showed for the very first time S-glutathionylation of mammalian p53R2 subunit that regulates DNA synthesis outside S-phase during DNA damage and repair. Taken together, these data will open new avenues for future research relating to exact physiological significance, target thiols, and/or overall RNR activity due to S-glutathionylation of R2 and p53R2 subunits and provide valuable insights for effective treatment regimes.

Quantitative assessments on induced high yielding mutant lines in urdbean [Vigna mungo (L.) hepper

AbstractVigna mungo (L.) hepper is an important grain legume with immense potential for establishing food security worldwide. However, the low genetic variability due to the self‐pollination mode of reproduction restricts its improvement endeavours. Therefore, the present study aimed at increasing the genetic variability and mean values of quantitative traits was undertaken by treating two widely cultivated varieties T‐9 and Pant U‐30, with low, intermediate and high doses of gamma rays and ethyl methanesulfonate in single and combination sets. The study accomplished selection of six mutant lines with augmented yield and manifold increase in genetic parameters, namely, genotypic coefficient of variation (GCV), heritability (h2), and genetic advance (GA) for economically important traits in M3 generation. A substantial increase in mean values of fertile branches per plant, pods per plant, and total plant productivity was noticed among the mutant lines. Phenotypic correlation between various character pairs showed a positive and significant relationship among the number of fertile branches, pods, total plant productivity, and negative association between the seed protein content and total plant yield in the selected mutant lines. In the control population, nitrate reductase activity (NRA), chlorophyll, carotenoid, and protein levels were significantly higher in M3 mutant lines in both varieties. The number and intensity of electrophoretic bands for seed protein in the mutant lines differed from the controls, indicating the mutagen induced polymorphism in protein bands among the mutant lines. In conclusion, the M3 high yielding mutant lines increased genetic variability, yield, protein, and pigment concentrations, isolated in this study, could serve as a valuable germplasm resource for black gram improvement programs.

Melatonin alleviates aluminum-induced growth inhibition by modulating carbon and nitrogen metabolism, and reestablishing redox homeostasis in Zea mays L.

Melatonin, a regulatory molecule, performs pleiotropic functions in plants, including aluminum (Al) stress mitigation. Here, we conducted transcriptomic and physiological analyses to identify metabolic processes associated with the alleviated Al-induced growth inhibition of the melatonin-treated (MT) maize (Zea mays L.) seedlings. Melatonin decreased Al concentration in maize roots and leaves under Al stress. Al stress reduced the total dry weight (DW) by 41.2% after 7 days of treatment. By contrast, the total DW was decreased by only 19.4% in MT plants. According to RNA-Seq, enzyme activity, and metabolite content data, MT plants exhibited a higher level of relatively stable carbon and nitrogen metabolism than non-treated (NT) plants. Under Al stress, MT plants showed higher photosynthetic rate and sucrose content by 29.9% and 20.5% than NT plants, respectively. Similarly, the nitrate reductase activity and protein content of MT plants were 34.0% and 15.0% higher than those of NT plants, respectively. Furthermore, exogenous supply of melatonin mitigated Al-induced oxidative stress. Overall, our results suggest that melatonin alleviates aluminum-induced growth inhibition through modulating carbon and nitrogen metabolism, and reestablishing redox homeostasis in maize.Graphical Abstarct [Display omitted]

Diagnostic application of sensitive and specific phage-exposed epitopes for visceral leishmaniasis and human immunodeficiency virus coinfection.

The diagnosis of visceral leishmaniasis (VL) has improved with the search of novel antigens; however, their performance is limited when samples from VL/human immunodeficiency virus (HIV)-coinfected patients are tested. In this context, studies conducted to identify more suitable antigens to detect both VL and VL/HIC coinfection cases should be performed. In the current study, phage display was performed using serum samples from healthy subjects and VL, HIV-infected and VL/HIV-coinfected patients; aiming to identify novel phage-exposed epitopes to be evaluated with this diagnostic purpose. Nine non-repetitive and valid sequences were identified, synthetized and tested as peptides in enzyme-linked immunosorbent assay experiments. Results showed that three (Pep2, Pep3 and Pep4) peptides showed excellent performance to diagnose VL and VL/HIV coinfection, with 100% sensitivity and specificity values. The other peptides showed sensitivity varying from 50.9 to 80.0%, as well as specificity ranging from 60.0 to 95.6%. Pep2, Pep3 and Pep4 also showed a potential prognostic effect, since specific serological reactivity was significantly decreased after patient treatment. Bioinformatics assays indicated that Leishmania trypanothione reductase protein was predicted to contain these three conformational epitopes. In conclusion, data suggest that Pep2, Pep3 and Pep4 could be tested for the diagnosis of VL and VL/HIV coinfection.

Optimizing Nitrogen Application in Root Vegetables from Their Growth, Biochemical and Antioxidant Response to Urea Fertilizer

Nitrogen is one of the most influencing inorganic nutrients for improved plant growth and yield in crops. However, excessive fertilizer application may have adverse impacts on the environment. Therefore, we strive to investigate in this work by examining the impact of different nitrogen (N) doses in the form of urea (46% N) on the growth, yield, photosynthetic pigment content, nitrate reductase activity, carbohydrate content, protein content, and antioxidant enzyme activity of the carrot and beetroot. A pot experiment was conducted under natural conditions with four nitrogen levels as basal treatment (Control = Nil N, U50 = 145.57 mg/kg N; U100 = 291.14 mg/kg N; U150 = 436.71 mg/kg N; U200 = 582.28 mg/kg N). Results found that U150 (436.71 mg/kg N) is the optimum N fertilizer dose at which significant (p ≤ 0.05) improvements in all the growth, yield and biochemical attributes of carrot and beetroot were observed. However, the further increment in N doses did not affect the observed parameters and, therefore, excessive N level was observed beyond U150 = 436.71 mg/kg N. The principal component analysis presented significant correlations among the various parameters observed. Two principal components account for a total of 98.86% variance (PC1 = 92.96%; PC2 = 5.90%) in carrot and 99.2% variance (PC1 = 92.64; PC = 6.56) in beetroot of the overall data variability in plants supplemented with different N treatments.