Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.7.1.2 (nitrate reductase)
 3,861 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mouse L929 fibroblastic cell line presents low, but detectable, levels of the mRNA encoding xanthine oxidoreductase under basal conditions, and it responds to type I and type II interferons by inducing the expression of the transcript [Falciani, Ghezzi, Terao, Cazzaniga, and Garattini (1992) Biochem. J. 285, 1001-1008]. This cell line, however, does not show any detectable amount of xanthine oxidoreductase enzymic activity, either before or after treatment with the cytokines. Molybdenum(VI) salts, in the millimolar range, are capable of activating xanthine oxidoreductase in L929 cells both under basal conditions and after treatment with interferon-alpha. The increase is observed in mouse L929 as well as in clones derived from it, but not in many other human and mouse cell lines. The induction observed in L929 cells is post-translational in nature and it is insensitive to cycloheximide, indicating that the molybdenum ion converts a pool of inactive xanthine oxidoreductase apoenzyme into its holoenzymic form. When grown in the absence of sodium molybdate, the L929 cell line has undetectable intracellular levels of the molybdenum cofactor, since the cell extracts are unable to complement the nitrate reductase defect of the nit-1 mutant of Neurospora crassa. L929 cells grown in the presence of millimolar concentrations of sodium molybdate, however, become competent to complement the nit-1 defect. L929 cells accumulate molybdenum ion inside the intracellular compartment as efficiently as TEnd cells, a mouse endothelial cell line that expresses xanthine oxidoreductase activity both under basal conditions and after treatment with interferon-gamma, suggesting that L929 cells have a defect in one or more of the metabolic steps leading to the synthesis of the molybdenum cofactor.
 ...
PMID:Molybdenum(VI) salts convert the xanthine oxidoreductase apoprotein into the active enzyme in mouse L929 fibroblastic cells. 812 33

Nitrate reductase (NR) gene fragments (1.1 kb and 800 bp) from the barley plant were incorporated into pSV2neo and transfected by electroporation into a variety of cell lines of different functionality. Only transfected murine macrophage cell lines demonstrated appreciably enhanced NO2- production (i.e., NR activity) both in the presence and absence of exogenous nitrate (NO3-). Addition of NO3- caused the greatest increase in NO2- production when macrophages were primed with interferon-gamma (INF-gamma) and lipopolysaccharide (LPS). Transfection of RAW 264.7 murine macrophages led to isolation of several novel neomycin-resistant subpopulations designated NR10(1), NR10(2) (both containing the 1.1 kb NR fragment) and NR800(5) (containing the 800 bp NR fragment). Similarly transfected nonleukocytic and leukocytic stem cell lines showed no significant NO2- production. Outside of the macrophage cell lines, only the murine T cell line EL-4 showed evidence of mild nitrite production enhancement. The mechanism of enhanced NO2- formation in NR transfected murine macrophages is unknown. However, study of these novel cells may lead to greater understanding of the expression of a plant NR in mammalian cells and highly controlled production of a cytotoxic molecule (NO2-) in macrophages.
 ...
PMID:Plant nitrate reductase gene fragments enhance nitrite production in activated murine macrophage cell lines. 819 85

The diagnosis of latent and active tuberculosis in the HIV-positive population is challenged by diminished sensitivity of conventional tests, atypical presentations, and the lack of culture methods in the developing world, where the burden of co-infection is greatest. In response to these challenges, a variety of new diagnostics have emerged. These include interferon-gamma release assays for the diagnosis of latent tuberculosis (TB) infection and novel culture methods and molecular assays for the diagnosis of active tuberculosis. Although some tests (such as interferon-gamma release assays) are not clearly superior to existing diagnostics, other novel diagnostics, such as real-time polymerase chain reaction and the microscopic observed direct susceptibility assay hold much promise for prompt and accurate TB diagnosis in this population. Line-probe, nitrate reductase, and mycobacteriophage assays have also provided rapid alternatives to conventional time-consuming drug susceptibility testing and are critical to curtailing the spread of multidrug-resistant TB.
 ...
PMID:Improving the diagnosis of tuberculosis: From QuantiFERON to new techniques to diagnose tuberculosis infections. 2166 Apr 59