180,152 results match your criteria enzymatic

Protective and Anti-Aging Effects of 5 Cosmeceutical Peptide Mixtures on Hydrogen Peroxide-Induced Premature Senescence in Human Skin Fibroblasts.

Skin Pharmacol Physiol 2021 Apr 13:1-9. Epub 2021 Apr 13.

Department of Oncology, Laboratory of Structural Biology, NHC Key Laboratory of Cancer Proteomics, Xiangya Hospital, Central South University, Changsha, China.

Skin aging usually leads to the excessive deterioration of the dermal extracellular matrix, loss of antimicrobial function, loss of skin barrier function, and a series of inflammatory processes. Bioactive peptides have been widely used in cosmetics due to their protective effects on skin and efficient absorption. Combination of different peptides may lead to synergistic or antagonistic effects, so different formulas need to be designed and tested properly. Read More

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Engineering a carbohydrate binding module to enhance chitinase catalytic efficiency on insoluble chitinous substrate.

Food Chem 2021 Mar 16;355:129462. Epub 2021 Mar 16.

College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China. Electronic address:

Development of a high-performance chitinase for efficient biotransformation of insoluble chitinous substrate would be highly valuable in industry. In this study, the chitin-binding domains (ChBDs) of chitinase SaChiA4 were successfully modified to improve the enzymatic activity. The engineered substitution variant R-SaChiA4, which had the exogenous ChBD of chitinase ChiA1 from Bacillus circulans WL-12 (ChBD) substituted for its original ChBD, increased its activity by nearly 54% (28. Read More

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Polypyrrole and enzyme free cholesterol flakes based composite: Selective determination of theophylline.

J Pharm Biomed Anal 2021 Apr 6;199:114065. Epub 2021 Apr 6.

Polymer Electronics Lab, Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi, 630 003, Tamil Nadu, India. Electronic address:

In the present work, we demonstrated the non-enzymatic theophylline (TP) detection using nanostructured Polypyrrole (Ppy) and Cholesterol (Ch) flakes coordinated nanocomposite coated on Glassy Carbon Electrode. The higher active surface area and good mechanical stability of the Ppy integrated Ch composite exhibited better oxidation towards TP. The electron transfer across hydrogen bonding is of fundamental importance in enhancing the biochemical process in this biosensor system. Read More

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Impact of chronic elevated ozone exposure on photosynthetic traits and anti-oxidative defense responses of Leucaena leucocephala (Lam.) de wit tree under field conditions.

Sci Total Environ 2021 Apr 6;782:146907. Epub 2021 Apr 6.

Plant Ecology and Climate Change Science Division, CSIR-National Botanical Research Institute, Lucknow, Uttar Pradesh 226001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India. Electronic address:

In this study, the impact of long term exposure of elevated ozone (+20 ppb above ambient) on photosynthetic traits and anti-oxidative defense system of Leucaena leucocephala, a tree of great economic importance, was studied in a Free Air Ozone Concentration Enrichment (O-FACE) facility at different time intervals (6, 12, 18, and 24 months). Results showed that net photosynthesis, photosynthetic pigments and lipid peroxidation were significantly reduced after 6, 12 and 24 months of exposure to elevated ozone (eO) whereas stomatal conductance and transpiration rate were significantly decreased after 12 months of exposure to eO. Antioxidant enzymatic activities (catalase, ascorbate peroxidase and glutathione reductase) were significantly increased after 12 months of exposure to eO Ascorbate was increased significantly after 6 and 12 months of exposure to eO while reduced glutathione content declined significantly after 6 and 24 months of exposure to eO. Read More

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A validated LC-MS/MS method for the quantification of climbazole metabolites in human urine.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Mar 29;1173:122677. Epub 2021 Mar 29.

Currenta GmbH & Co. OHG, Institute of Biomonitoring, Chempark Gebäude Q 18, D-51368 Leverkusen, Germany.

Climbazole is a preservative and an anti-dandruff ingredient with applications in various cosmetic products. The general population is therefore exposed to this chemical, and exposure monitoring is desirable. We have postulated a pathway for the human metabolism of climbazole, leading to two specific metabolites which can be excreted via urine. Read More

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Attenuation of the extracellular matrix increases the number of synapses but suppresses synaptic plasticity through upregulation of SK channels.

Cell Calcium 2021 Apr 8;96:102406. Epub 2021 Apr 8.

Department of Molecular Neurobiology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street 16/10, Moscow, 117997, Russia; Department of Physiology, Jiaxing University College of Medicine, Zhejiang, 314033 China; Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Str 19с1, Moscow, 119146, Russia. Electronic address:

The effect of brain extracellular matrix (ECM) on synaptic plasticity remains controversial. Here, we show that targeted enzymatic attenuation with chondroitinase ABC (ChABC) of ECM triggers the appearance of new glutamatergic synapses on hippocampal pyramidal neurons, thereby increasing the amplitude of field EPSPs while decreasing both the mean miniature EPSC amplitude and AMPA/NMDA ratio. Although the increased proportion of 'unpotentiated' synapses caused by ECM attenuation should promote long-term potentiation (LTP), surprisingly, LTP was suppressed. Read More

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Droplet-Based Microfluidic High-Throughput Screening of Enzyme Mutant Libraries Secreted by Yarrowia lipolytica.

Methods Mol Biol 2021 ;2307:205-219

Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.

Yarrowia lipolytica has emerged as an attractive solution for screening enzyme activities thanks to the numerous tools available for heterologous protein production and its strong secretory ability. Nowadays, activity screening for improved enzymes mostly relies on the evaluation of independent clones in microtiter plates. However, even with highly robotized screening facilities, the relatively low throughput and high cost of the technology do not enable the screening of large diversities, which significantly reduce the probability of isolating improved variants. Read More

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January 2021

Methods to Activate and Elucidate Complex Endogenous Sugar Metabolism in Yarrowia lipolytica.

Methods Mol Biol 2021 ;2307:175-189

Department of Chemical and Biomolecular Engineering, University of Tennessee, Knoxville, TN, USA.

Yarrowia lipolytica has endogenous metabolism to use complex sugars derived from lignocellulosic biomass. However, many of these pathways are cryptic and hence either inactive or inefficient for xylose, arabinose, and cellobiose assimilation. Here we present collective methods to activate and elucidate these endogenous sugar pathways by performing short-term growth adaptation, determining the pathway efficiency, and conducting transcriptomic, enzymatic, and metabolic analyses to identify rate limiting steps for enhanced sugar consumption. Read More

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January 2021

Measuring the Complex Effects of the Single-Stranded DNA-Binding Protein gp2.5 on Primer Synthesis and Extension by the Bacteriophage T7 Replisome.

Methods Mol Biol 2021 ;2281:323-332

Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA.

The single-stranded DNA-binding protein gp2.5 of bacteriophage T7 plays myriad functions in the replication of phage genomes. In addition to interacting with ssDNA, gp2. Read More

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January 2021

Analysis of Mitochondrial SSB-DNA Complexes and Their Effects on DNA Polymerase γ Activity by Electron Microscopy and Enzymatic Assays.

Methods Mol Biol 2021 ;2281:265-272

Department of Chemistry, Auburn University at Montgomery, Montgomery, AL, USA.

The mitochondrial single-stranded DNA-binding protein (mtSSB) regulates the function of the mitochondrial DNA (mtDNA) replisome. In vitro, mtSSB stimulates the activity of enzymatic components of the replisome, namely mtDNA helicase and DNA polymerase gamma (Pol γ). We have demonstrated that the stimulatory properties of mtSSB result from its ability to organize the single-stranded DNA template in a specific manner. Read More

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January 2021

Breaching self-tolerance by targeting the gatekeeper.

J Exp Med 2021 May;218(5)

Department of Pediatrics and Drukier Institute for Children's Health, Weill Cornell Medicine, New York, NY.

Loss-of-function mutations in DNaseL13, the enzyme that restricts the amount of microparticle-associated DNA, cause SLE in humans and mice. In this issue of JEM, Hartl et al. (2021. Read More

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Dual-Mode FEN1 Activity Detection Based on Nt.BstNBI-Induced Tandem Signal Amplification.

Anal Chem 2021 Apr 13. Epub 2021 Apr 13.

Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.

Flap endonuclease 1 (FEN1) is a structure-specific nuclease that cleaves the 5' single-stranded protrusion (also known as 5' flap) during Okazaki fragment processing. It is overexpressed in various types of human cancer cells and has been considered as an important biomarker for cancer diagnosis. However, conventional methods for FEN1 assay usually suffer from complicated platform and laborious procedures with a limited sensitivity. Read More

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Maturation of bovine oocytes under low culture temperature decreased glutathione peroxidase activity of both oocytes and blastocysts.

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Pol J Vet Sci 2021 Mar;24(1):93-99

Ondokuz Mayis University, Faculty of Agriculture, Department of Agricultural Biotechnology, 55139, Samsun, Turkey.

It is known that the basic variable in the cellular environment is temperature and low temperature decreases cellular metabolism rate. Also, low cellular metabolic activity reduces oxidative stress, resulting in low ROS production. The aim of this study was therefore to investigate the effect of 36. Read More

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Comparison of biomarker responses after acute and chronic bioassays in Lumbriculus variegatus.

Environ Sci Pollut Res Int 2021 Apr 12. Epub 2021 Apr 12.

Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Toxicología y Química Legal, Universidad de Buenos Aires, Ciudad Universitaria, Pab. II. 4to piso, Pabellón II, C1428EGA, Buenos Aires, Argentina.

Differential biomarker responses may occur after acute or chronic bioassays when animals are unfed. In many aquatic species, food deprivation may lead to a pro-oxidant condition. However, information about its effects on the oligochaete Lumbriculus variegatus, a bioindicator organism for water and sediment toxicity tests, is almost completely lacking. Read More

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Engineering of a borneol dehydrogenase from P. putida for the enzymatic resolution of camphor.

Appl Microbiol Biotechnol 2021 Apr 12. Epub 2021 Apr 12.

Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, Schulgasse 11a, 94315, Straubing, Germany.

Several thousand different terpenoid structures are known so far, and many of them are interesting for applications as pharmaceuticals, flavors, fragrances, biofuels, insecticides, or fine chemical intermediates. One prominent example is camphor, which has been utilized since ancient times in medical applications. Especially (-)-camphor is gaining more and more interest for pharmaceutical applications. Read More

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Cisplatin enhances protein ‑GlcNAcylation by altering the activity of OGT, OGA and AMPK in human non‑small cell lung cancer cells.

Int J Oncol 2021 Jun 13;58(6). Epub 2021 Apr 13.

National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, Qingdao, Shandong 266237, P.R. China.

‑GlcNAcylation is a dynamic and reversible post‑translational modification of proteins that is modulated by ‑GlcNAc transferase (OGT) and ‑GlcNAcase (OGA). Alterations in the protein expression of ‑linked β‑‑acetylglucosamine (‑GlcNAc) can be induced by multiple factors. However, little is known of the effects of chemotherapeutic agents on ‑GlcNAcylation and the relevant molecular mechanisms in cancer cells. Read More

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Plasma Concentrations of Magnesium and Risk of Dementia: A General Population Study of 102 648 Individuals.

Clin Chem 2021 Apr 13. Epub 2021 Apr 13.

Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark.

Background: Low and high concentrations of plasma magnesium are associated with increased risk of future all-cause dementia; however, the underlying reasons remain elusive. The magnesium ion is an important electrolyte serving as a cofactor in many enzymatic processes in the human organism. Magnesium affects both neuronal and vascular functions. Read More

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