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MBio Jan 2019J. Hiras, S. V. Sharma, V. Raman, R. A. J. Tinson, et al. (mBio 9:e01603-18, 2018, https://doi.org/10.1128/mBio.01603-18) report on the identification of a novel thiol,...
J. Hiras, S. V. Sharma, V. Raman, R. A. J. Tinson, et al. (mBio 9:e01603-18, 2018, https://doi.org/10.1128/mBio.01603-18) report on the identification of a novel thiol, N-methyl-bacillithiol (N-Me-BSH), in the green sulfur bacterium In N-methyl-bacillithiol, the amine of the cysteine is methylated by a novel -adenosylmethioneine transferase designated N-methyl-bacillithiol synthase A (NmbA). The Hiras et al. study is significant because it is the first report of the presence of N-Me-BSH in anaerobic bacteria.
Topics: Bacteria, Anaerobic; Chlorobi; Cysteine; Glucosamine; Sulfhydryl Compounds
PubMed: 30647158
DOI: 10.1128/mBio.02634-18 -
Scientific Reports Dec 2023Nanobiotechnology is a unique class of multiphase and recently become a branch of contemporary science and a paradigm shift in material research. One of the two main...
Nanobiotechnology is a unique class of multiphase and recently become a branch of contemporary science and a paradigm shift in material research. One of the two main problems facing the field of nanomaterial synthesis is the discovery of new natural resources for the biological production of metal nanoparticles and the absence of knowledge about the chemical composition of bio-source required for synthesis and the chemical process or mechanism behind the production of metal nanoparticles presents the second difficulty. We reported template-free green synthesized copper oxide nanoparticles using Tribulus terrestris seed natural extract without any isolation process. XRD, TEM, SEM, UV-Vis, DLS, zeta potential, and BET evaluated the synthesized metal nanoparticle. The TEM analysis confirmed that the CuO NPs are well dispersed and almost round in shape with an average size of 58 nm. EDAX confirms that copper is the prominent metal present in the nanomaterial. The greener fabricated copper oxide nanoparticle was employed to degrade methyl orange dye, almost 84% of methyl orange was degraded within 120 min. The outcomes demonstrated the nanomaterial's effective breakdown of contaminants, highlighting their potential for environmental rehabilitation. The electrochemical investigation of the CuO NPs was utilized for supercapacitor application. An appreciable value of specific capacitance is 369 F/g specific capacitances with 96.4% capacitance retention after 6000 cycles. Overall, the results of the current study show that the biologically produced copper oxide nanoparticles have intriguing uses as photocatalysts for treating water contaminants and are suitable for energy storage devices.
Topics: Copper; Tribulus; Nanoparticles; Metal Nanoparticles; Oxides; Seeds; Plant Extracts; Spectroscopy, Fourier Transform Infrared
PubMed: 38110542
DOI: 10.1038/s41598-023-49706-w -
The Biochemical Journal Apr 19701. By means of (14)C tracer experiments and isotope competition experiments the roles of d-tyrosine, p-hydroxyphenylpyruvic acid, p-hydroxyphenylacetic acid,...
Biosynthesis of phytoquinones. Homogentisic acid: a precursor of plastoquinones, tocopherols and alpha-tocopherolquinone in higher plants, green algae and blue-green algae.
1. By means of (14)C tracer experiments and isotope competition experiments the roles of d-tyrosine, p-hydroxyphenylpyruvic acid, p-hydroxyphenylacetic acid, phenylacetic acid, homogentisic acid and homoarbutin (2-methylquinol 4-beta-d-glucoside) in the biosynthesis of plastoquinones, tocopherols and alpha-tocopherolquinone by maize shoots was investigated. It was established that d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid can all be utilized for this purpose, whereas p-hydroxyphenylacetic acid, phenylacetic acid and homoarbutin cannot. Studies on the mode of incorporation of d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid showed that their nuclear carbon atoms and the side-chain carbon atom adjacent to the nucleus give rise (as a C(6)-C(1) unit) to the p-benzoquinone rings and nuclear methyl groups (one in each case) of plastoquinone-9 and alpha-tocopherolquinone and the aromatic nuclei and nuclear methyl groups (one in each case) of gamma-tocopherol and alpha-tocopherol. 2. By using [(14)C]-homogentisic acid it has been shown that homogentisic acid is also a precursor of plastoquinone, tocopherols and alpha-tocopherolquinone in the higher plants Lactuca sativa and Rumex sanguineus, the green algae Chlorella pyrenoidosa and Euglena gracilis and the blue-green alga Anacystis nidulans.
Topics: Carbon Isotopes; Chlorophyta; Cyanobacteria; Phenylacetates; Phenylpyruvic Acids; Plants; Quinones; Tyrosine; Vitamin E
PubMed: 4986835
DOI: 10.1042/bj1170593 -
Scientific Reports Oct 2018Although the major green tea catechins can inhibit the activity of carbohydrate-hydrolyzing enzymes, there is a paucity of information describing the potential of other...
Although the major green tea catechins can inhibit the activity of carbohydrate-hydrolyzing enzymes, there is a paucity of information describing the potential of other green tea ingredients and numerous green tea cultivars. Herein, we reveled that a green tea cultivar Sunrouge significantly suppressed the postprandial blood glucose level in mice. Unlike the most representative Japanese green tea cultivar, Yabukita, the suppression by Sunrouge was observed clearly during the initial period after oral dosing of starch. Sunrouge also strongly inhibited the carbohydrate-hydrolyzing enzymes α-glucosidase and α-amylase when compared with that of Yabukita and many other cultivars. Liquid chromatography-mass spectrometry (LC-MS)-based metabolic profiling (MP) of 42 Japanese green tea cultivars was performed. Multivariate statistical analysis enabled visualization of the differences among cultivars with respect to their ability to inhibit carbohydrate-hydrolyzing activities. Analysis of metabolites, contributing to the discrimination and prediction of the bioactivity of cultivars, showed that O-methylated catechins, epicatechin-3-O-(3-O-methyl) gallate (ECG3"Me) and epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me), were newly identified α-glucosidase inhibitors. Such ability was also observed in epigallocatechin-3-O-gallate (EGCG), epicatechin-3-O-gallate (ECG), delphinidin-3-O-glucoside and myricetin-3-O-glucoside. The amounts of these compounds in Sunrouge were higher than that in many other cultivars. These results suggest that Sunrouge has high potential for suppressing the elevation of the postprandial blood glucose level, and an MP approach may become a valuable strategy for evaluating the anti-hyperglycemic activity of green tea and for screening its active ingredients.
Topics: Animals; Blood Glucose; Carbohydrate Metabolism; Chromatography, Liquid; Dose-Response Relationship, Drug; Hypoglycemic Agents; Metabolome; Metabolomics; Mice; Phytochemicals; Plant Extracts; Postprandial Period; Tandem Mass Spectrometry; Tea
PubMed: 30375449
DOI: 10.1038/s41598-018-34316-8 -
IET Nanobiotechnology Apr 2019This investigation has for the first time utilised environmental resource seed extract phytochemicals for the green synthesis of carpogenic ZnO nanoparticles (NPs)....
This investigation has for the first time utilised environmental resource seed extract phytochemicals for the green synthesis of carpogenic ZnO nanoparticles (NPs). Spherical morphology and size range of 56.57-107.70 nm at variable calcination temperatures without the use of any external reducing agent was obtained. The synthesised NPs exhibited hexagonal wurtzite geometry with an average crystal size 5.62 nm and a band gap of 3.4 eV. Carpogenic NPs were investigated for optical, compositional, morphological, and phytochemical make up via ultraviolet spectroscopy (UV-Vis), Fourier transform infrared analysis, X-ray powder diffraction, scanning electron microscopy, and gas chromatography and mass spectrometry. Carpogenic NPs degraded methyl red up to 83% with pseudo-first-order degradation kinetics ( = 0.88) in 18 min signifying their remediation role in environment in conformity with all principles of green chemistry. Photocatalytic assays were performed in direct solar irradiance. Nine pathogens of biomedical and agricultural significance having multi-drug resistance were inhibited in vitro via the Kirby-Bauer disc diffusion assay. The enhanced photocatalytic and antimicrobial inhibition not only makes carpogenic ZnO NPs a future photo-degradative candidate for environmental remediation but also a nanofertiliser, nanofungicide, and nanobactericide synthesised via bioinspired, biomimetic, green, and unprecedented route.
Topics: Anti-Infective Agents; Azo Compounds; Bacteria; Green Chemistry Technology; Metal Nanoparticles; Particle Size; Plant Extracts; Prunus domestica; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction; Zinc Oxide
PubMed: 31051445
DOI: 10.1049/iet-nbt.2018.5006 -
Journal of Visualized Experiments : JoVE May 2015Methyl green has long been known as a histological stain with a specific affinity for DNA, although its fluorescent properties have remained unexplored until recently....
Methyl green has long been known as a histological stain with a specific affinity for DNA, although its fluorescent properties have remained unexplored until recently. In this article, we illustrate the method for preparing a methyl green aqueous stock solution, that when diluted can be used as a very convenient fluorescent nuclear label for fixed cells and tissues. Easy procedures to label whole zebrafish and chick embryos are detailed, and examples of images obtained shown. Methyl green is maximally excited by red light, at 633 nm, and emits with a relatively sharp spectrum that peaks at 677 nm. It is very inexpensive, non-toxic, highly stable in solution and very resistant to photobleaching when bound to DNA. Its red emission allows for unaltered high resolution scanning confocal imaging of nuclei in thick specimens. Finally, this methyl green staining protocol is compatible with other cell staining procedures, such as antibody labeling, or actin filaments labeling with fluorophore-conjugated phalloidin.
Topics: Animals; Cell Nucleus; Chick Embryo; Coloring Agents; DNA; Embryo, Nonmammalian; Embryology; Fluorescent Dyes; Methyl Green; Staining and Labeling; Zebrafish
PubMed: 25993383
DOI: 10.3791/52769 -
Bio-protocol Jan 2018Triacylglycerols (TAGs) are esters formed from one glycerol and three fatty acids. TAGs are induced to accumulate in algal cells under environmental stress conditions...
Triacylglycerols (TAGs) are esters formed from one glycerol and three fatty acids. TAGs are induced to accumulate in algal cells under environmental stress conditions including nutrient-limitation, hyperosmosis, and low temperature, for the storage of metabolic energy and carbon, and also for the consumption of excess energy (, Hirai , 2016 ; Hayashi , 2017 ). Beside their physiological significance, the commercial utilization of algal TAG has been expected for the production of biodiesel, the methyl esters of fatty acids, from the aspect of carbon-neutral conception. The amounts of TAGs can be determined through quantitative measurement of their constituent fatty acids. This protocol consists of the following three parts: the first is the extraction of total lipids from algal cells with the use of organic solvents, chloroform and methanol, according to the method of Bligh and Dyer (1959), the second is the separation of TAG from the other lipid classes by thin-layer chromatography (TLC), and the third is the production of methyl-esterified derivatives of their constitutive fatty acids and subsequent quantitation of them by capillary gas-liquid chromatography (GLC). This protocol adapted from Sato and Tsuzuki (2011) is used for TAG analysis in a green alga, .
PubMed: 34179230
DOI: 10.21769/BioProtoc.2676 -
Arthritis Research & Therapy Mar 2020Skin fibrosis is the clinical hallmark of systemic sclerosis (SSc), where collagen deposition and remodeling of the dermis occur over time. The most widely used outcome...
BACKGROUND
Skin fibrosis is the clinical hallmark of systemic sclerosis (SSc), where collagen deposition and remodeling of the dermis occur over time. The most widely used outcome measure in SSc clinical trials is the modified Rodnan skin score (mRSS), which is a semi-quantitative assessment of skin stiffness at seventeen body sites. However, the mRSS is confounded by obesity, edema, and high inter-rater variability. In order to develop a new histopathological outcome measure for SSc, we applied a computer vision technology called a deep neural network (DNN) to stained sections of SSc skin. We tested the hypotheses that DNN analysis could reliably assess mRSS and discriminate SSc from normal skin.
METHODS
We analyzed biopsies from two independent (primary and secondary) cohorts. One investigator performed mRSS assessments and forearm biopsies, and trichrome-stained biopsy sections were photomicrographed. We used the AlexNet DNN to generate a numerical signature of 4096 quantitative image features (QIFs) for 100 randomly selected dermal image patches/biopsy. In the primary cohort, we used principal components analysis (PCA) to summarize the QIFs into a Biopsy Score for comparison with mRSS. In the secondary cohort, using QIF signatures as the input, we fit a logistic regression model to discriminate between SSc vs. control biopsy, and a linear regression model to estimate mRSS, yielding Diagnostic Scores and Fibrosis Scores, respectively. We determined the correlation between Fibrosis Scores and the published Scleroderma Skin Severity Score (4S) and between Fibrosis Scores and longitudinal changes in mRSS on a per patient basis.
RESULTS
In the primary cohort (n = 6, 26 SSc biopsies), Biopsy Scores significantly correlated with mRSS (R = 0.55, p = 0.01). In the secondary cohort (n = 60 SSc and 16 controls, 164 biopsies; divided into 70% training and 30% test sets), the Diagnostic Score was significantly associated with SSc-status (misclassification rate = 1.9% [training], 6.6% [test]), and the Fibrosis Score significantly correlated with mRSS (R = 0.70 [training], 0.55 [test]). The DNN-derived Fibrosis Score significantly correlated with 4S (R = 0.69, p = 3 × 10).
CONCLUSIONS
DNN analysis of SSc biopsies is an unbiased, quantitative, and reproducible outcome that is associated with validated SSc outcomes.
Topics: Adult; Algorithms; Azo Compounds; Biopsy; Cohort Studies; Deep Learning; Eosine Yellowish-(YS); Female; Humans; Male; Methyl Green; Middle Aged; Neural Networks, Computer; Principal Component Analysis; Scleroderma, Localized; Scleroderma, Systemic; Severity of Illness Index; Skin
PubMed: 32171325
DOI: 10.1186/s13075-020-2127-0 -
Journal of Neurophysiology Jan 2019Traumatic brain injuries introduce functional and structural circuit deficits that must be repaired for an organism to regain function. We developed an injury model in...
Traumatic brain injuries introduce functional and structural circuit deficits that must be repaired for an organism to regain function. We developed an injury model in which Xenopus laevis tadpoles are given a penetrating stab wound that damages the optic tectal circuit and impairs visuomotor behavior. In tadpoles, as in other systems, injury induces neurogenesis. The newly generated neurons are thought to integrate into the existing circuit; however, whether they integrate via the same mechanisms that govern normal neuronal maturation during development is not understood. Development of the functional visuomotor circuit in Xenopus is driven by sensory activity. We hypothesized that enhanced visual experience would improve recovery from injury by facilitating integration of newly generated neurons into the tectal circuit. We labeled newly generated neurons in the injured tectum by green fluorescent protein expression and examined their circuit integration using electrophysiology and in vivo imaging. Providing animals with brief bouts of enhanced visual experience starting 24 h after injury increased synaptogenesis and circuit integration of new neurons and facilitated behavioral recovery. To investigate mechanisms of neuronal integration and behavioral recovery after injury, we interfered with N-methyl-d-aspartate (NMDA) receptor function. Ifenprodil, which blocks GluN2B-containing NMDA receptors, impaired dendritic arbor elaboration. GluN2B blockade inhibited functional integration of neurons generated in response to injury and prevented behavioral recovery. Furthermore, tectal GluN2B knockdown blocked the beneficial effects of enhanced visual experience on functional plasticity and behavioral recovery. We conclude that visual experience-mediated rehabilitation of the injured tectal circuit occurs by GluN2B-containing NMDA receptor-dependent integration of newly generated neurons. NEW & NOTEWORTHY Recovery from brain injury is difficult in most systems. The study of regenerative animal models that are capable of injury repair can provide insight into cellular and circuit mechanisms underlying repair. Using Xenopus tadpoles, we show enhanced sensory experience rehabilitates the injured visual circuit and that this experience-dependent recovery depends on N-methyl-d-aspartate receptor function. Understanding the mechanisms of rehabilitation in this system may facilitate recovery in brain regions and systems where repair is currently impossible.
Topics: Animals; Brain Injuries; Excitatory Amino Acid Antagonists; Gene Knockdown Techniques; Green Fluorescent Proteins; Larva; Neural Pathways; Neurogenesis; Neuronal Plasticity; Neurons; Photic Stimulation; Piperidines; Receptors, N-Methyl-D-Aspartate; Recovery of Function; Synapses; Visual Perception; Xenopus laevis
PubMed: 30517041
DOI: 10.1152/jn.00664.2018 -
The Journal of General Physiology Jan 1950Study of the stoichiometry of the DNA-methyl green reaction by dialysis, precipitation of stain-nucleic acid mixtures, and the staining of nuclei of known DNA content,...
Study of the stoichiometry of the DNA-methyl green reaction by dialysis, precipitation of stain-nucleic acid mixtures, and the staining of nuclei of known DNA content, indicate that the compound consists of one dye molecule per 10 P. The significance of this result was discussed in the preceding paper (1). Histone and lanthanum (and probably other multivalent cations (3)) compete with the dye for the nucleic acid molecule, indicating a common site of attachment, presumably the phosphoric acid groups. With care in the avoidance of procedures which might depolymerize DNA, and the use of a buffer at about pH 4.1, a quantitative histochemical method for DNA by the use of methyl green is possible. Pyronin staining appears to be of qualitative significance only. Slight differences in degree of polymerization, as between the shad and mammalian DNA appear to have no effect on methyl green staining. It may be that a critical level of polymerization for DNA staining exists. This level must exceed 20 nucleotides to account for the 10 P to 1 dye molecule and the effect on the methyl green absorption spectrum; but it may be considerably greater. Beyond this critical level, whatever it may be, further polymerization probably has no influence on staining.
Topics: Animals; Buffers; DNA; Methyl Green; Nucleic Acids; Nucleotides; Phosphoric Acids; Pyronine; Staining and Labeling
PubMed: 15409512
DOI: 10.1085/jgp.33.3.265