The energy landscapes of proteins are highly complex and can be influenced by changes in physical and chemical conditions under which the protein is studied. The redox enzyme cytochrome P450cam undergoes a multistep catalytic cycle wherein two electrons are transferred to the heme group and the enzyme visits several conformational states. Using paramagnetic NMR spectroscopy with a lanthanoid tag, we show that the enzyme bound to its redox partner, putidaredoxin, is in a closed state at ambient temperature in solution. This result contrasts with recent crystal structures of the complex, which suggest that the enzyme opens up when bound to its partner. The closed state supports a model of catalysis in which the substrate is locked in the active site pocket and the enzyme acts as an insulator for the reactive intermediates of the reaction.
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http://dx.doi.org/10.1073/pnas.1502351112 | DOI Listing |
Plants (Basel)
January 2025
Department of Turf Science and Engineering, College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.
White clover () is an excellent perennial cold-season ground-cover plant for municipal landscaping and urban greening. It is, therefore, widely distributed and utilized throughout the world. However, poor salt tolerance greatly limits its promotion and application.
View Article and Find Full Text PDFNutrients
January 2025
Department of Nutrition, School of Public Health, Sun Yat-sen University (Northern Campus), 74 Zhongshan Road II, Guangzhou 510080, China.
Background: Brussels chicory affluent in phenolic acids could inhibit atherosclerosis; however, its effects on exercise performance and post-exercise recovery are unknown. We hypothesized that Brussels chicory could enhance exhaustive aerobic exercise performance and post-exercise recovery by promoting lactate oxidation.
Methods: This is a single-blind, randomized, placebo-controlled two-way cross-over trial involving 32 untrained college students (men 18) who consumed either Brussels chicory juice (100 g of Brussels chicory containing ~130 mg phenolic acids and 180 mL fresh milk) or placebo (180 mL fresh milk) for 7 days with a 2-week washout period.
Nutrients
January 2025
Department of Public Health & Exercise Science, Appalachian State University, Boone, NC 28607, USA.
Background: Quercetin (QCT) and citrulline (CIT) have been independently associated with improved antioxidant capacity and nitric oxide (NO) production, potentially enhancing cardiovascular function and exercise performance. This study aimed to evaluate the combined and independent effects of QCT and CIT supplementation on NO metabolites and antioxidant biomarkers in 50 trained cyclists undergoing a 20 km cycling time trial (TT).
Methods: In a randomized, double-blind, placebo-controlled design, forty-two male and eight female trained cyclists were assigned to QCT + CIT, QCT, CIT, or placebo (PL) groups.
Pharmaceuticals (Basel)
January 2025
Department of Chemistry and Biochemistry, Medical Faculty, Trakia University, 11 Armeiska Str., 6000 Stara Zagora, Bulgaria.
Gentamicin (GM) administration is associated with decreased metabolism, increased oxidative stress, and induction of nephrotoxicity. L., containing flavonoids, anthocyanins, and phytosterols, possesses antioxidant and anti-inflammatory potential.
View Article and Find Full Text PDFMolecules
January 2025
Department of Chemistry and Biochemistry, University of Colorado, Colorado Springs, CO 80918, USA.
Catalytically active nanomaterials, or nanozymes, have gained significant attention as alternatives to natural enzymes due to their low cost, ease of preparation, and enhanced stability. Because of easy preparation, excellent biocompatibility, and unique optoelectronic properties, gold nanoparticles (AuNPs) have attracted increasing attention in many fields, including nanozymes. In this work, we demonstrated the applicability of beta-cyclodextrin functionalized gold nanoparticles (β-CD-AuNPs) as enzyme mimics for different substances, including TMB and DA.
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