Cytochrome P-450 reductase (encoded by the NCP1 gene) was found to catalyse all the NADPH-dependent ferrireductase activities associated with isolated plasma membranes of the yeast Saccharomyces cerevisiae. We therefore examined the contribution of this enzyme to the ferrireductase activity of cells in vivo. Cytochrome P-450 reductase was shown to be not essential for the cell ferrireductase activity, but it influenced this activity, with different effects on the Fre1- and the Fre2-dependent reductase systems. Overexpression of FRE1 did not lead to an increased ferrireductase activity of the cells when NCP1 was repressed. In contrast, cells that overexpressed FRE2 had maximal ferrireductase activity when NCP1 was repressed. The degree of NCP1 expression also affected the amount of iron and copper accumulated by the cells during growth. The biochemical implications and the physiological significance of these observations are discussed.
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http://dx.doi.org/10.1111/j.1574-6968.1997.tb12720.x | DOI Listing |
J Biol Inorg Chem
December 2024
Departamento de Fisiología, Biofísica y Neurociencias, Cinvestav, 07360, Mexico City, Mexico.
The rise of atmospheric oxygen as a result of photosynthesis in cyanobacteria and chloroplasts has transformed most environmental iron into the ferric state. In contrast, cells within organisms maintain a reducing internal milieu and utilize predominantly ferrous iron. Ferric reductases are enzymes that transfer electrons to ferric ions, either extracellularly or within endocytic vesicles, enabling cellular ferrous iron uptake through Divalent Metal Transporter 1.
View Article and Find Full Text PDFPlant Physiol Biochem
December 2024
Plant Molecular Biology Laboratory, Department of Botany, Dayanand Anglo-Vedic (PG) College, Chhatrapati Shahu Ji Maharaj University, Kanpur, 208 001, India. Electronic address:
Mol Microbiol
December 2024
Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA.
Pathogenic fungi must appropriately sense the host availability of essential metals such as Fe. In Candida albicans and other yeasts, sensing of Fe involves mitochondrial Fe-S clusters. Yeast mutants for Fe-S cluster assembly sense Fe limitation even when Fe is abundant and hyperaccumulate Fe.
View Article and Find Full Text PDFPlant Physiol Biochem
December 2024
MED - Mediterranean Institute for Agriculture, Environment and Development & CHANGE-Global Change and Sustainability Institute, Faculty of Science and Technology, Building 8, University of Algarve, Campus of Gambelas, 8005-139, Faro, Portugal.
Iron (Fe) chlorosis is very common in plants cultivated in calcareous soils of the Mediterranean basin and is usually corrected by the application of Fe chelates to the soil, which can have a negative impact on the environment. The aim of this experiment was to assess the role of quercetin, a natural compound widely present in plants and known to bind Fe, in correcting Fe chlorosis when supplied in the Hoagland nutrient solution. In this context, strawberry plants were grown at different Fe concentrations, with 0 (Fe0), 1 (Fe1) and 5 (Fe5) μM of Fe in the nutrient solution, until the onset of clear Fe chlorosis symptoms.
View Article and Find Full Text PDFJ Neurophysiol
August 2024
School of Basic Medicine, Qingdao University, Qingdao, China.
Alpha-synuclein (α-syn) is a major component of Lewy bodies, which is a biomarker of Parkinson's disease (PD). It accumulates in substantia nigra pars compacta (SNpc) to form insoluble aggregates and cause neurotoxicity, which is often accompanied by iron deposition. We compared the iron reductase activity between monomeric α-syn (M-α-syn) and oligomeric α-syn (O-α-syn) and investigated the effect of α-syn on iron metabolism of BV2 microglia cells as well.
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