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关键词： Cloning   Halophilic α-amylase   Nesterenkonia sp   strain F   Gene analysis   Biochemical characterization   3D structure prediction   DNA-DNA HYBRIDIZATION   GENOME SEQUENCE   NUCLEOTIDE-SEQUENCE   PURIFICATION   WEB   EXTREMOPHILES   SPECIFICITY   INDUSTRIAL   ENZYMES   SEARCH  

摘要： A novel pH and thermo-tolerate halophilic alpha-amylase from moderately halophilic bacterium, Nesterenkonia *** F was cloned and expressed in Escherichia coli. 16S rRNA sequence of the strain shared 99.46% similarities with closely related type species. Also, the genome sequence shared ANI values below 92% and dDDH values below 52% with the closely related type species. Consequently, it is proposed that strain F represents a novel species. The AmyF gene was 1390 bp long and encodes an alpha-amylase of 463 amino acid residues with pI of 4.62. The deduced AmyF shared very low sequence similarity (< 24%) with functionally characterized recombinant halophilic alpha-amylases. The recombinant alpha-amylase was successfully purified from Ni-NTA columns with a molecular mass of about 52 KDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The enzyme was active over a wide range of temperature (25-75 degrees C) and pH (4-9) with optimum activity at 45 degrees C and 7.5, respectively. Also, although it was active over a various concentrations of NaCl and KCl (0-4 M), increasing activity of the enzyme was observed with increasing concentration of these salts. Low concentrations of Ca2+ ion had no activating effect, but high concentrations of the ion (40-200 mM) enhanced activity of AmyF. The enzyme activity was increased by increasing concentrations of Mg2+, Zn2+, Hg2+ and Fe3+. However, it was inhibited only at very high concentrations of these metal ions. Cu2+ did not decrease the amylase activity and the highest activity was observed at 100 mM of the ion. These properties indicate wide potential applications of this recombinant enzyme in starch processing industries. This is the first isolation, cloning and characterization of a gene encoding alpha-amylase from Nesternkonia genus.

关键词： Vigna unguiculata   Chemical characterization   Functional properties   Antioxidant activities   Hoggar   NUTRITIONAL QUALITY   VARIETY   FLOUR   TIME  

摘要： Cowpea is among the most grain legumes consumed in Algeria. The Algerian Saharan is a hostile environment characterized by high temperatures, scarcity of water and salinity of water and soil. In these regions, the farmers have for generations cultivated landraces cowpeas which are probably adapted to these particular environments and which may have particular nutritional and functional characteristics. These cowpeas deserve to be known and exploited in breeding and improvement programs. This study aims to determine the nutritional value and functional properties of Saharan cowpea through their chemical composition and the analysis of biochemical variability between accessions taking into consideration the environments of origin. Eighteen cowpea landraces were harvested in an arid region of southern Algeria (Hoggar, Tamanrasset). The seeds composition was evaluated by the determination of certain chemical characteristics such as moisture ash, crude protein, fat, total carbohydrates, and energy value. The antioxidant activity was also evaluated which includes total non-enzymatic antioxidant capacity (CANET) and lipid peroxidation, which were determined by conventional methods. The results showed variability among the accessions studied (p >= 0.05), and that all the landraces had high crude protein and total carbohydrates. The total non-enzymatic antioxidant capacity (CANET) recorded is low, as well as lipid peroxidation. The moisture content, ash content and fat content were also low in these saharan cowpea accessions. The Functional properties of the flour were also evaluated. The water absorption capacity (WAC) varies with an average of 1.17 g/gMS, the oil absorption capacity (OAC) with an average of 0.4 g/gMs, and the swelling index (SI) with an average of 2.63. The accessions NEA7 and NEA13 are the richest in protein and they have the highest nutritional value. We report here for the first time that cowpea seeds grown in the Hoggar region have high biochemical var

关键词： Enoki mushroom   Macromolecules   Substrate   Biochemical changes   Minerals   HPLC   FLAMMULINA-VELUTIPES   GROWTH   WILD   RESIDUES   ENZYMES   STRAINS  

摘要： Purpose This study, for the first time, investigated the pattern of changes in a range of macromolecules and minerals of a lignocellulosic substrate utilized for cultivation of Enoki mushroom. Methods Five different phases of a lignocellulosic substrate (consisting of 40% wheat straw + 40% sawdust + 18% wheat bran) were examined, including raw, mycelia-filled, pinning, fruiting, and the spent substrates. A well-authenticated native strain of Enoki mushroom, Flammulina velutipes, was used for cultivation in the substrate. Results The results exhibited a significant 1.35-fold, 1.18-fold, and 1.30-fold increase in nitrogen, soluble carbohydrates, and ash contents of the spent substrate, respectively, compared to the raw substrate. Conversely, a remarkable reduction was observed in holocellulose (27%), insoluble lignin (27%), insoluble carbohydrates (33%), and C:N ratio (33%) in the spent substrate, compared to the raw substrate. Soluble lignin increased by 23% in the mycelia-filled phase compared to the raw substrate, but it returned to its initial level in the spent substrate. Further HPLC coupled with GC-MS confirmed the lignin changes and demonstrated that the ratio of syringyl to guaiacyl (as lignin monolignols) increased towards the fructification phases. There was also a significant increase in the contents of elements in the spent substrate compared to the raw substrate. Conclusion The data presented here provide evidences for understanding how biochemical changes in macromolecules of a lignocellulosic substrate could lead to optimum vegetative growth and fructification of Enoki mushroom, leaving a high-value non-toxic spent substrate. [GRAPHICS] .

关键词： Chlorophyta   Biodiesel   Biomass   Lipids   Lipid droplet   Microalgae   LIPID-ACCUMULATION   ISOCHRYSIS-GALBANA   BIODIESEL   CHLORELLA   STARCH   ALGAE   CHLAMYDOMONAS   ENHANCEMENT   CHLOROPHYTA   DEPRIVATION  

摘要： In recent years biodiesel production has attracted worldwide attention due to the awareness of fossil fuel depletion and microalgae biomass is considered a promising raw material for its formulation. The present study evaluated the effects of different levels of nitrogen limitation (37.5, 18.75, 9.375 mg L-1 NaNO3) on the growth, cell ultrastructure, and biochemical composition of a halophilic native strain of the green alga Picocystis salinarum as a potential raw material source for biodiesel. During a culture period of 20 days, growth measurements and photosynthetic pigments were estimated. Cell density, dry weight, and chlorophylls a, b content decreased with time as nitrogen limitation increase; however, carotenoid content increased. In addition, nitrogen limitation caused an progressive increase in the lipid and carbohydrate yield and a decrease in protein. The high N limitation (9.375 mg L-1) had a significant effect on the accumulation of total lipid content (33.87% dry weight). Carbohydrate content (30.98% dry weight) and protein content (1.89% dry weight) decrease. The lipid content showed a differential FAME profile with high saturated fatty acid values (996.08 mu g g(-1) dry weight) mainly palmitic acid, compare with the unsaturated ones that showed low values under high N limitation. The gradual increase of lipid content was also corroborated by transmission electron microscopy images with a single large lipid droplet cell formation. Therefore, evaluation of the algal culture conditions such as N limitation, as a strategy to maximize lipid content and improve the fatty acid profile in unexplored strain of P. salinarum, showed a potential biomass yield as a suitable candidate for biodiesel production.

关键词： Bacteriophage BUCT555   Stenotrophomonas maltophilia   Genomic analysis   Phage proteins   Podoviridae   RESISTANT PSEUDOMONAS-AERUGINOSA   BOVINE MASTITIS   PHAGE   SEQUENCE   DATABASE   THERAPY   SEARCH  

摘要： Stenotrophomonas maltophilia is a common conditional pathogen, and it is naturally resistant to most commonly used clinical antibiotics. The bacteriophage is considered to be a potential antibiotic alternative for treating multi-drug-resistant bacteria. In this study, a bacteriophage BUCT555 was isolated from hospital sewage for lysing the clinical multi-drug resistant Stenotrophomonas maltophilia. Electron microscopy studies revealed this phage belongs to the Podoviridae family. The double-stranded DNA genome of bacteriophage BUCT555 is composed of 39,440 bp with a GC content of 61.43%. The genome contains 57 open reading frames, 14 of which had assigned functions, while no virulence related genes, antibiotic resistance genes or tRNA were identified. The burst size of BUCT555 was 204 pfu per infected cell. Structure proteins of bacteriophage BUCT555 generated by SDS-PAGE and HPLC-MS revealed that it contains seven proteins with molecular weight ranging from 19 to 89 kDa. BLASTn analysis showed that phage BUCT555 has 2% homology with other phages in NCBI database, suggesting BUCT555 is a new phage genus of Podoviridae that infects Stenotrophomonas maltophilia. Characterization of the bacteriophage BUCT555 enriches our knowledge about the diversity of Stenotrophomonas maltophilia bacteriophages.

关键词： Salt-wasting tubulopathies   Salt-retaining tubulopathies   Distal renal tubular acidosis   Renal Fanconi Syndrome   Bartter Syndromes   Gitelman Syndrome   EAST Syndrome   Pseudohypoaldosteronism   Liddle syndrome   Apparent Mineralocorticoid Excess   ION-TRANSPORT   MUTATIONS   ACIDOSIS   DIAGNOSIS   CHILDREN  

摘要： Evolution moves in mysterious ways. Excretion of waste products by glomerular filtration made perfect sense when life evolved in the ocean. Yet, the associated loss of water and solutes became a problem when life moved onto land: a serious design change was needed and this occurred in the form of ever more powerful tubules that attached to the glomerulus. By reabsorbing typically more than 99% of the glomerular filtrate, the tubules not only minimise urinary losses, but, crucially, also maintain homeostasis: tubular reabsorption and secretion are adjusted so as to maintain an overall balance, in which urine volume and composition matches intake and environmental stressors. A whole orchestra of highly specialised tubular transport proteins is involved in this process and dysfunction of one or more of these results in the so-called kidney tubulopathies, characterised by specific patterns of clinical and biochemical abnormalities. In turn, recognition of these patterns helps establish a specific diagnosis and pinpoints the defective transport pathway. In this review, we will discuss these clinical and biochemical "fingerprints" of tubular disorders of salt-handling and how sodium handling affects volume homeostasis but also handling of other solutes.

关键词： Plateletpheresis   Citrate   Calcium   Magnesium   Parathyroid hormone   APHERESIS DONORS   MAGNESIUM   CALCIUM   ANTICOAGULATION  

摘要： Objectives. - During plateletpheresis, citrate induces hypocalcemia and hypomagnesemia, which are usually transient and self-limiting, but they can lead to significant donor discomfort. The aim of study was to determine the effect of citrate infusion on a multitude of biochemical parameters during plateletpheresis in healthy donors and to correlate changes with adverse donor reactions. Methods. - The study was conducted on 60 healthy plateletpheresis donors. Blood samples were drawn on three occasions, a baseline pre-donation sample, 30 min at start of procedure and 30 min post procedure. Heparinized samples were taken to measure ionized calcium and plain samples to measure serum calcium, serum magnesium, parathyroid hormone, total protein and serum albumin. Results. - There was statistically significant decline in mean total calcium (9.27 +/- 0.66 mg/dl to 8.72 +/- 0.87 mg/dl) and ionized calcium (3.8 + 0.51 mg/dl to 2.9 + 0.67 mg/dl) from baseline until 30 min after the start of procedure respectively. A significant fall in serum magnesium, total protein and serum albumin was observed. The mean parathyroid hormone showed significant increase from baseline levels till at the completion of procedure (19.94 +/- 12.1 pg/ml to 92.08 +/- 36.78 pg/ml). If the yield was set constant, there was negative correlation between ACD used and pre-donation platelet count. Majority of adverse donor reactions were hypocalcemic reactions, which were more with Amicus double yield plateletpheresis and were managed with calcium supplementation. Conclusion. - Plateletpheresis induces marked reduction in serum calcium and magnesium levels. Moreover, increase in parathyroid hormone levels was significant. In addition, decline in total protein and serum albumin may be a concern in donors also participating in plasmapheresis. (C) 2021 Societe francaise de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.

关键词： Glyphosate   N-acetylcysteine   Liver   Malondialdehyde   Histopathology   Ultrastructure   Caspase-3   Proliferating cell nuclear antigen   NUCLEAR ANTIGEN PCNA   OXIDATIVE STRESS   CASPASE-3 ACTIVATION   SUBCHRONIC EXPOSURE   ANTIOXIDANT THERAPY   LIVER   APOPTOSIS   HERBICIDE   CELLS   TOXICITY  

摘要： Glyphosate (GLP) is the most commonly used herbicide that presents many hazards to the environment and living organisms. The present study aimed to explore hepatotoxic properties of GLP on adult albino rats, and the ability of N-acetylcysteine (NAC) to ameliorate these toxic effects. Thirty mature male albino rats were distributed into 3 groups (10 rats/group): Group I (C) a negative control, Group II (GLP) orally administered Roundup 0.8503 ml/kg/day which contain GLP (375 mg/kg) (1/10 of LD50) by gavage needle, and Group III (NAC+ GLP) received NAC (160 mg/kg, 1h before Roundup) by gavage needle and Roundup (0.8503 ml/kg) orally for 6 weeks. Blood and liver samples were collected and processed for biochemical, histopathological, ultrastructural, and immunohistochemical investigations. Group II displayed a significant elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) levels, as well as overexpression of apoptotic markers. The total antioxidant capacity "TAC" and mRNA expression of NRF2 were significantly decreased. Concerning the histopathological findings, there were various degenerative changes as the hepatocytes showed hydropic swelling with nuclear pyknosis. These alterations were confirmed ultrastructurally as most of the cytoplasmic organelles were lost and the mitochondria appeared to deteriorate. Immunohistochemical results showed intense immunoreactivity against proliferating cell nuclear antigen (PCNA) and caspase-3. NAC administration before GLP partially ameliorates these alterations. ALT, AST, and MDA levels as well as expression of apoptotic markers were significantly reduced. TAC and mRNA expression of NRF2 were significantly increased. Histopathological alterations were partially improved as the hepatocytes returned normal and ultrastructurally they showed nearly normal cytoplasmic organelles. Additionally, the intense expression of PCNA and caspase-3 was significantly reduced. We concluded that

关键词： Ga-68-PSMA   F-18-FDG   Biochemical recurrence   Negative PSMA   F-18-FLUORODEOXYGLUCOSE PET/CT   PSMA-LIGAND   UTILITY   C-11-CHOLINE   EXPRESSION   PATTERNS   RELAPSE  

摘要： Purpose Ga-68-PSMA PET/CT has a high detection rate in prostate cancer patients with biochemical recurrence (BCR). However, few studies have reported other imaging methods for BCR with negative Ga-68-PSMA PET/CT findings. We investigated the value of F-18-FDG compared with Ga-68-PSMA and identified BCR patients with Ga-68-PSMA-negative findings who are most likely to benefit from F-18-FDG PET/CT. Methods Seventy-two BCR patients with negative Ga-68-PSMA PET/CT findings were retrospectively identified from 510 patients who underwent concomitant Ga-68-PSMA and F-18-FDG PET/CT between June 2018 and August 2020. Patients were categorised into groups with positive or negative F-18-FDG PET/CT findings. Differences in patients' characteristics between these two groups and predictors of positive F-18-FDG findings were analysed. Results The detection rate of F-18-FDG PET/CT was 16.7% (12/72) in BCR patients with Ga-68-PSMA-negative findings. PSA and Gleason score were significantly higher in the F-18-FDG-positive group than in the F-18-FDG-negative group (P < 0.001 and P < 0.001, respectively). A multivariate analysis indicated that PSA (PSA >= 2.3 ng/mL) and Gleason score (Gleason score >= 8) correlated with F-18-FDG-positive findings (P < 0.001 and P = 0.015, respectively). The probabilities of F-18-FDG-positive findings in the low-potential (PSA <2.3 ng/mL and Gleason score <8), moderate-potential (PSA <2.3 ng/mL and Gleason score >= 8 or PSA >= 2.3 ng/mL and Gleason score <8), and high-potential (PSA >= 2.3 ng/mL and Gleason score >= 8) groups were 0%, 11.5%, and 90.0%, respectively (P < 0.001). Conclusion PSA level and Gleason score are independent predictors of F-18-FDG-positive findings, and BCR patients with Ga-68-PSMA-negative findings with high PSA and Gleason score are most likely to benefit from F-18-FDG PET/CT.

关键词： Biolog GEN III system   Biochemical characterization   Rhizobacteria   Seedling growth   Seedling vigor   Upland rice  

摘要： Plant growth-promoting rhizobacteria (PGPR) are known to stimulate plant growth because of their versatility in nutrient transformation. However, the success of PGPR inoculation depends not only on their ability to promote plant growth but also on their capacity to metabolize substrates that can be used as energy for the development and survival of the crops. Given the important influence of seed germination and vigor on crop yield, this study investigated the biochemical characteristics and effectiveness of multi-trait PGPR isolates in enhancing upland rice seedling growth and vigor. Biochemical identification was done using Biolog GEN III Microbial Identification System. Isolates were characterized based on their ability to metabolize all major classes of biochemicals in the carbon source utilization and chemical sensitivity assays. Identified rhizobacterial isolates were tested in vitro to evaluate their inoculation effects on the growth of PSB Rc23 upland rice seedlings. Biochemical identification results showed that rhizobacterial isolates have extensive metabolic activities in a wide range of carbon sources. Inoculation effects revealed that isolate IBBw(1a) was the most effective in enhancing root length and vigor index of rice seedlings in vitro, yielding a significant increase of 60% and 53%, respectively, over the uninoculated control. This study suggests that rhizobacterial isolates from upland rice may have commercial significance to improve seedling growth and vigor. These isolates will undergo a further assessment of their effectiveness in actual upland rice field conditions as they were already proven effective growth promoters in laboratory and screenhouse conditions. Such future activity can uncover their efficacy as potential biofertilizers in the actual soil environment.