Chronic granulomatous disease (CGD) is due to a functional defect of the O2- generating NADPH oxidase of phagocytes. Epstein-Barr-virus-immortalized B lymphocytes express all the constituents of oxidase with activity 100 times less than that of neutrophils. As in neutrophils, oxidase activity of Epstein-Barr-virus-immortalized B lymphocytes was shown to be defective in the different forms of CGD; these cells were used as a model for the complementation studies of two p67-phox-deficient CGD patients. Reconstitution of oxidase activity was performed in vitro by using a heterologous cell-free assay consisting of membrane-suspended or solubilized and purified cytochrome b558 that was associated with cytosol or with the isolated cytosolic-activating factors (p67-phox, p47-phox, p40-phox) from healthy or CGD patients. In p67-phox-deficient CGD patients, two cytosolic factors are deficient or missing: p67-phox and p40-phox. Not more than 20% of oxidase activity was recovered by complementing the cytosol of p67-phox-deficient patients with recombinant p67-phox. On the contrary, a complete restoration of oxidase activity was observed when, instead of cytosol, the cytosolic factors were added in the cell-free assay after isolation in combination with cytochrome b558 purified from neutrophil membrane. Moreover, the simultaneous addition of recombinant p67-phox and recombinant p40-phox reversed the previous complementation in a p40-phox dose-dependent process. These results suggest that in the reconstitution of oxidase activity, p67-phox is the limiting factor; the efficiency of complementation depends on the membrane tissue and the cytosolic environment. In vitro, the transition from the resting to the activated state of oxidase, which results from assembling, requires the dissociation of p40-phox from p67-phox for efficient oxidase activity. In the process, p40-phox could function as a negative regulatory factor and stabilize the resting state.
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http://dx.doi.org/10.1046/j.1432-1327.2000.01097.x | DOI Listing |
PeerJ
January 2025
College of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
Background: Geraniol 10-hydroxylase (G10H) is a cytochrome P450 monooxygenase involved in regulation, which is involved in the biosynthesis of monoterpene. However, G10H is not characterized at the enzymatic mechanism and regulatory function in .
Methods And Results: A gene related to the biosynthesis of monoterpenoid, geraniol 10-hydroxylase, has been cloned from the medicinal plant .
Clin Transl Sci
January 2025
Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
In neurovascular settings, including treatment and prevention of ischemic stroke and prevention of thromboembolic complications after percutaneous neurointerventional procedures, dual antiplatelet therapy with a P2Y12 inhibitor and aspirin is the standard of care. Clopidogrel remains the most commonly prescribed P2Y12 inhibitor for neurovascular indications. However, patients carrying CYP2C19 no-function alleles have diminished capacity for inhibition of platelet reactivity due to reduced formation of clopidogrel's active metabolite.
View Article and Find Full Text PDFSmall
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
Nitrogen doping emerges as a potent approach to enhance the oxidase-like activity of carbon nanozymes. However, the unclear knowledge of the active nitrogen species within nitrogen-doped carbon nanozymes hinders the advancement of high-performance carbon nanozymes. Herein, a group of nitrogen-doped carbon (N/C) nanozymes with controllable nitrogen dopants are successfully synthesized via a dicyandiamide-assisted pyrolysis method.
View Article and Find Full Text PDFEcotoxicology
January 2025
Department of Zoology, Guru Nanak Dev University, Amritsar, Punjab, India.
Spodoptera litura (Lepidoptera: Noctuidae) is one of the most destructive insect pests. Insecticides remain the principal management tool to control this pest. However, indiscriminate use of insecticides has resulted in the development of resistance to a variety of insecticides in S.
View Article and Find Full Text PDFPlant Mol Biol
January 2025
Department of Plant Pathology, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra (GKVK), Bengaluru, India.
In a wake of shifting climatic scenarios, plants are frequently forced to undergo a spectrum of abiotic and biotic stresses at various stages of growth, many of which have a detrimental effect on production and survival. Naturally, microbial consortia partner up to boost plant growth and constitute a diversified ecosystem against abiotic stresses. Despite this, little is known pertaining to the interplay between endophytic microbes which release phytohormones and stimulate plant development in stressed environments.
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