Genetic Polymorphism and Natural Selection of Apical Membrane Antigen-1 in Plasmodium falciparum Isolates from Vietnam

Apical membrane antigen-1 of Plasmodium falciparum (PfAMA-1) is a leading malaria vaccine candidate antigen. However, the genetic diversity of pfama-1 and associated antigenic variation in global P. falciparum field isolates are major hurdles to the design of an efficacious vaccine formulated with this antigen. Here, we analyzed the genetic structure and the natural selection of pfama-1 in the P. falciparum population of Vietnam. A total of 37 distinct haplotypes were found in 131 P. falciparum Vietnamese isolates. Most amino acid changes detected in Vietnamese pfama-1 were localized in the ectodomain, domains I, II, and III. Overall patterns of major amino acid changes in Vietnamese pfama-1 were similar to those of global pfama-1, but the frequencies of the amino acid changes slightly differed by country. Novel amino acid changes were also identified in Vietnamese pfama-1. Vietnamese pfama-1 revealed relatively lower genetic diversity than currently analyzed pfama-1 in other geographical regions, and suggested a distinct genetic differentiation pattern. Evidence for natural selection was detected in Vietnamese pfama-1, but it showed purifying selection unlike the global pfama-1 analyzed so far. Recombination events were also found in Vietnamese pfama-1. Major amino acid changes that were commonly identified in global pfama-1 were mainly localized to predicted B-cell epitopes, RBC-binding sites, and IUR regions. These results provide important information for understanding the genetic nature of the Vietnamese pfama-1 population, and have significant implications for the design of a vaccine based on PfAMA-1.

Investigation of major amino acid residues of anti-norfloxacin monoclonal antibodies responsible for binding with fluoroquinolones

It is important to understand the amino acid residues that govern the properties of the binding between antibodies and ligands. We studied the binding of two anti-norfloxacins, anti-nor 132 and anti-nor 155, and the fluoroquinolones norfloxacin, enrofloxacin, ciprofloxacin, and ofloxacin. Binding cross-reactivities tested by an indirect competitive enzyme-linked immunosorbent assay indicated that anti-nor 132 (22–100%) had a broader range of cross-reactivity than anti-nor 155 (62–100%). These cross-reactivities correlated with variations in the numbers of interacting amino acid residues and their positions. Molecular docking was employed to investigate the molecular interactions between the fluoroquinolones and the monoclonal antibodies. Homology models of the heavy chain and light chain variable regions of each mAb 3D structure were docked with the fluoroquinolones targeting the crucial part of the complementarity-determining regions. The fluoroquinolone binding site of anti-nor 155 was a region of the HCDR3 and LCDR3 loops in which hydrogen bonds were formed with TYR (H:35), ASN (H:101), LYS (H:106), ASN (L:92), and ASN (L:93). These regions were further away in anti-nor 132 and could not contact the fluoroquinolones. Another binding region consisting of HIS (L:38) and ASP (H:100) was found for norfloxacin, enrofloxacin, and ciprofloxacin, whereas only ASP (H:100) was found for ofloxacin.

Nutritional Values of Onion Bulbs with Some Essential Structural Parameters for Packaging Process

Onions belong to the Allium genus that has been frequently used for human diet and the traditional medication due to the bioactive compounds. The main nutritional values, vitamins, and amino acid compositions of onion bulbs (Yellow, Red, Green, Leek, and Baby onions) with some essential structural parameters for the packaging process were investigated. Physical and structural parameters with frictions were applied for the packaging process. The results reported that moisture content was the main component of onion bulbs (88.65%). Besides, they were rich in proteins (9.22–13.21 g/100 g infresh weight) (FW). Results reported that Red and Yellow varieties established the largest vitamin C and carotenoids contents (45.07 mg/100 g−1 FW) and (1.44 µg/mL FW), respectively. The major amino acid was arginine which was highly found in Green variety (17.02 mg/g FW) and a relatively high amount of glutamic and aspartic acids as (9.88–14.89 mg/g FW) and (4.93–10.55 mg/g FW), respectively. Yellow variety established the largest width, thickness, surface area, aspect ratio, and sphericity. The highest static and kinetic frictions were established on steel (0.14–0.52) and (0.75–0.96), respectively. This study presents the nutritional evidence of onion varieties for the human diet besides the horticultural processing for packaging quality improvement.

The Composition, Physicochemical Properties, Antioxidant Activity, and Sensory Properties of Estonian Honeys

Thirty honey samples from different regions of Estonia were investigated to determine the chemical compositions, physicochemical properties, bioactive compounds, and sensory characteristics of typical honeys from a northern climate. The physicochemical parameters, such as electrical conductivity, moisture content, free acidity, hydroxymethylfurfural, diastase, and invertase activity were measured. The color was measured and expressed by L*-, a*-, and b*-coordinates. Sensory parameters were determined by using “fruity”, “floral”, “berry-like”, “herbal”, “woody”, “spicy”, “sweet”, and “animal-like” as the main odor and flavor attributes. The total polyphenol and flavonoid contents were in the range of 26.2–88.7 mg gallic acid equivalents (GAE) per 100 g and 1.9–6.4 mg quercetin equivalents (QE) per 100 g, respectively. The identified polyphenols showed the highest intensities of caffeic acid, coumaric acid, and abscisic acid and its derivatives. The protocatechuic acid intensity was highest in honeys containing traces of honeydew elements and of cinnamic acid and myricetin in heather honey. The water-soluble antioxidant values were 37.8–311.2 mg ascorbic acid equivalents (AAE) per 100 g and the lipid soluble antioxidant values were 14.4–60.7 mg Trolox equivalents (TE) per 100 g. The major amino acid in the analyzed honeys was proline, with variable values depending on the honey’s botanical source. Correlations were calculated based on the results obtained. It was revealed that the typical Estonian honey has floral, berry-like, sweet, and rather mild sensory characteristics. Most of the honeys lacked stronger spicy, woody, and animal-like attributes. The typical color of Estonian honey is quite light.

Genetic characterisation and local genotypes of canine parvovirus strains collected from pet dogs in central and eastern China during 2018–2019

IntroductionCanine parvovirus type-2 (CPV-2) causes acute infectious diseases in puppies, which show high morbidity and mortality. Better effect of vaccination against these diseases could be achieved with deeper knowledge of CPV-2 genotype dissemination and mutation history. This study investigated CPV-2–positive samples collected recently over a wide region of China.Material and MethodsA total of 118 faecal samples from dogs identified as CPV-positive were collected from veterinary clinics in central and eastern China. Overall, 16 strains collected from Anhui, 29 from Henan, and 16 from Zhejiang Province were sequenced to determine the genotypic composition of CPV-2 and mutational complexity of CPV-VP2.ResultsThe CPV-2a, CPV-2b, and CPV-2c genotypes were detected in Anhui and Henan Provinces, while CPV-2c alone was detected in Zhejiang Province. Sequence analysis of all strains showed 98.5%–99.8%, 98.3%–99.9%, and 98.7%–99.8% identity among the 16 Anhui, 29 Henan, and 16 Zhejiang strains, respectively. Strains collected from Anhui and Henan Provinces showed lower identity (97.0%), suggesting greater genetic divergence in central China. The mutation rates of Henan and Anhui strains were lower than that of Zhejiang strains. Major amino acid mutations occurred at sites 5, 370, 426, and 440. Epitope and entropy analyses implied these sites’ likely conformance to the principles of mutation tendency, complexity, and diversity.ConclusionThe findings for the evolutionary structure of CPV-2 strains collected from three provinces in central and eastern China advance trend monitoring of the genetic variation in canine parvovirus and point to its implications in the development of novel vaccines.

High Levels of Major Components and Antioxidant Activity of Fermented Tea Treated with Lactococcus lactis subsp. cremoris

Tea is a popular drink all over the world and has been attracting attention for its beneficial health effects. We developed a fermented tea by processing it with an exopolysaccharides-producing lactic acid bacterium, Lactococcus lactis subsp. cremoris, in order to manufacture high-quality tea with a physiological function. Lactococcus lactis subsp. cremoriswas added to tea leaves (Camellia sinensis) and fermented for two weeks. To examine the progress of fermentation, we determined the change in pH as well as the contents of ascorbic acid and folic acid in the extract of leaves. Decreases in ascorbic and folic acids were identified, but pH only slightly changed during fermentation, showing a slower development of fermentation with lactic acid bacteria. Furthermore, we analyzed the extract’s components, such as catechins, amino acids, including theanine as the major amino acid, and caffeine. Although there were some fluctuations in contents, no significant change was seen over a period of two weeks. Fermentation had no effect on the degradation of these components, suggesting that they may be relatively stable. To investigate a potential physiological function, antioxidant activity was measured using 1,1-Diphenyl-2-picryl-hydrazyl, (DPPH). Consequently, the results showed that the activity of the extracts was unaffected by fermentation until the seventh day, when it began to increase. Our results suggested that the fermented tea developed in this study, which maintained its key components of catechins, theanine and caffeine, exhibit a physiological function as a processed tea and a novel food material.

Beclabuvir can Inhibit the RNA-dependent RNA Polymerase of Newly Emerged Novel Coronavirus (SARS-CoV-2)

Recent emergence of novel coronavirus (SARS-CoV-2) all over the world has resulted more than 33,106 global deaths. To date well-established therapeutics modules for infected patients are unknown. In this present initiative, molecular interactions between FDA-approved antiviral drugs against the Hepatitis-C virus (HCV) have been investigated theoretically against the RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. HCV and SARS-CoV-2 are both +ssRNA viruses. At 25o C beclabuvir, a non-nucleoside inhibitor of the RdRpHCV can efficiently bind to RdRp SARS-CoV-2 (ΔGAutoDock = -9.95 kcal mol-1) with an inhibition constant of 51.03 nM. Both the ΔGLondon and ΔGGBVI / WSA values were - 9.06 and - 6.67 kcal mol-1, respectively for binding of beclabuvir to RdRpSARS-CoV-2. In addition, beclabuvir has also shown better binding free energy with RdRpSARS-CoV-2 (ΔGvina = -8.0 kcal mol-1) than that observed with the Thumb 1 domain of RdRpHCV (ΔGvina = -7.1 kcal mol-1). InterProScan has suggested the RNA-directed 5'-3' polymerase activity exists within 549th to 776th amino acid residues of RdRpSARS-CoV, where the major amino acid residues interacting being I591, Y621, C624, D625, A690, N693, L760, D762, D763, and E813-N817. Molecular interaction suggests occupancy of beclabuvir inside the active site environment of the RdRpSARS-CoV-2, the enzyme essential for viral RNA synthesis. In conclusion, results suggest beclabuvir may serve as an anti-SARS-CoV-2 drug.

Investigation of chemical constituents of Artemisia albicerata

Artemisia albicerata is of great interest and occupy an important place among the vast variety of medicinal plants in Kazakhstan due to its endemicity, medical and pharmacological properties, and has a rich chemical composition consisting of amino acids, fatty acids, macro-micro elements, flavonoids and other low-molecular substances. In the present study, Artemisia albicerata, collected in Almaty region of Kazakhstan has been explored with the purpose of quantitative and qualitative analysis. As a result, twenty amino and eight fatty acids were identified by gas-liquid chromatography. The major amino acid contents were glutamate (2615 mg/100 g), aspartate (1296 mg/100 g) and alanine (890 mg/100 g), while the composition of fatty acids mainly was oleic (19.6%) and linoleic (68.4%) acids. Furthermore, eleven macro-micro elements were determined in the ash of a plant by the method of multi-element atomic emission spectral analysis, main of them were Ca (60.0 mg/g), K (60.4 mg/g), Mg (12.2 mg/g), Na (5.57 mg/g), Fe (3.57 mg/g). Also it should be highlighted that total bioactive components such as organic acids, flavonoids, tannins, coumarins, alkaloids, saponins, polysaccharides together with the moisture content (6.62%), total ash (7.96%) and extractives (12.7%) have been determined.

Stress-Reducing Function of Matcha Green Tea in Animal Experiments and Clinical Trials

Theanine, a major amino acid in green tea, exhibits a stress-reducing effect in mice and humans. Matcha, which is essentially theanine-rich powdered green tea, is abundant in caffeine. Caffeine has a strong antagonistic effect against theanine. The stress-reducing effect of matcha was examined with an animal experiment and a clinical trial. The stress-reducing effect of matcha marketed in Japan and abroad was assessed based on its composition. The stress-reducing effect of matcha in mice was evaluated as suppressed adrenal hypertrophy using territorially-based loaded stress. High contents of theanine and arginine in matcha exhibited a high stress-reducing effect. However, an effective stress-reducing outcome was only possible when the molar ratio of caffeine and epigallocatechin gallate (EGCG) to theanine and arginine was less than two. Participants (n = 39) consumed test-matcha, which was expected to have a stress-reducing effect, or placebo-matcha, where no effect was expected. Anxiety, a reaction to stress, was significantly lower in the test-matcha group than in the placebo group. To predict mental function of each matcha, both the quantity of theanine and the ratios of caffeine, EGCG, and arginine against theanine need to be verified.

Evidence for the oxidant-mediated amino acid conversion, a naturally occurring protein engineering process, in human cells

Reactive oxygen species (ROS) play an important role in the development of various pathological conditions as well as aging. ROS oxidize DNA, proteins, lipids, and small molecules. Carbonylation is one mode of protein oxidation that occurs in response to the iron-catalyzed, hydrogen peroxide-dependent oxidation of amino acid side chains. Although carbonylated proteins are generally believed to be eliminated through proteasome-dependent degradation, we previously discovered the protein de-carbonylation mechanism, in which the formed carbonyl groups are chemically eliminated without proteins being degraded. Major amino acid residues that are susceptible to carbonylation include proline and arginine, both of which are oxidized to become glutamyl semialdehyde, which contains a carbonyl group. The further oxidation of glutamyl semialdehyde produces glutamic acid. Thus, we hypothesize that through the ROS-mediated formation of glutamyl semialdehyde, the proline, arginine, and glutamic acid residues within the protein structure are interchangeable. In support of this hypothesis, mass spectrometry demonstrated that proline 45 (a well-conserved residue within the catalytic sequence) of the peroxiredoxin 6 molecule can be converted into glutamic acid in cultured human cells, establishing a revolutionizing concept that biological oxidation elicits the naturally occurring protein engineering process.