Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.6.99.3 (diaphorase)
 5,903 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have investigated a relationship between two detoxication systems, metabolic detoxication through the cytochrome P-450 (P-450) pathway and resistance to infection through interferon (IFN), in mice infected with influenza virus following exposure to coal dust (CD) and diesel exhaust (DE) particulates. Mice were exposed by inhalation to filtered air (FA; control), CD, or DE for 1 month and then inoculated intranasally (IN) with influenza virus. During infection, 7-ethoxycoumarin deethylase (7ECdeEt'ase) and ethylmorphine demethylase (EMdeMe'ase) (monooxygenases), and NADPH cytochrome c reductase (NADPH c red'ase) were measured in liver microsomes. Temporal patterns of enzyme activities were observed with control animals. EMdeMe'ase and NADPH c red'ase exhibited peak values at Day 4 postinfection (27.6 and 482 nmole/min/mg protein, respectively), compared to initial activities (9.1 and 307 nmole/min/mg protein, respectively). 7ECdeEt'ase activity decreased between Days 1-3 postvirus infection and thereafter returned to the original value (1.7 nmole/min/mg protein). When the mice were first exposed to CD or DE particulates for 1 month prior to influenza infection, changes in enzyme temporal patterns were observed. The increased EMdeMe'ase activity at Day 4 was not observed in mice exposed to CD and was reduced in mice exposed to DE. Preexposure to either particulate resulted in the abolition of the increased Day 4 activity of NADPH c red'ase. The 7ECdeEt'ase postinfection temporal pattern was not affected by a preexposure to either particulate. Estimates of the enzyme activities after the 1-month exposure to FA, CD, or DE but before virus infection indicated no changes due to particulate exposure alone. Under these conditions of particulate exposure and virus infection, serum IFN levels in the mice used in this study peaked at Days 4-5 and were unaffected by the 1-month preexposure to CD or DE (Hahon et al., (1985). The data suggest the relationship that exists between metabolic detoxication and resistance to infection in normal mice was altered during a short-term preexposure to CD or DE.
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PMID:Influenza virus-induced alterations of cytochrome P-450 enzyme activities following exposure of mice to coal and diesel particulates. 242 23

The present study provides a direct experimental evidence that the combination of influenza A/Aichi/2/68 (H3N2) infection with different models of "oxidative stress", such as immobilization, cold and cold-restraint, is associated with graduated oxidative disturbances in the liver of mice, despite the absence of virus and inflammation in this tissue. It was found that experimental influenza virus infection is accompanied with a significant increase of lipid peroxidation products, a decrease of natural antioxidants (vitamin E, glutathione) and cytochrome P-450, an inhibition of cytochrome c reductase and liver monooxygenases (analgin- N-demethylase and amidopyrine- N-demethylase). Immobilization and cold stress, applied separately or in combination (cold-restraint), did not influence significantly any of the analysed parameters compared to those of the control group of non-infected mice. Preliminary exposure of mice to immobilization or cold stress and subsequent inoculation of influenza virus resulted in a significant increase of lipid peroxidation products and a significant decrease of vitamin E and reduced glutathione, compared with levels in control (non-infected) animals. Compared to influenza virus-infected and non-stressed animals, the changes in all these parameters were negligible. Immobilization or cold stress, applied in combination with influenza virus infection, partially prevented the suppressive effect of influenza virus on cytochrome P-450 and liver monooxygenases. A tendency towards normalization of these parameters to the control levels was observed. However, after application of cold-restraint plus influenza virus infection, the level of cytochrome P-450 and activity of cytochrome c reductase stayed markedly lower than in infected and non-stressed animals. The activities of liver monooxygenases were slightly increased compared with those of infected and non-stressed animals, but stayed relatively low compared to control (non-infected) mice. Combination of cold-restraint and influenza virus infection resulted in a greater synergistic increase of lipid peroxidation products and a greater synergistic decrease of vitamin E and reduced glutathione compared to controls, as well as to influenza virus-infected and non-stressed animals.
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PMID:Effect of immobilization, cold and cold-restraint stress on liver monooxygenase activity and lipid peroxidation of influenza virus-infected mice. 1191 79

DPNH cytochrome c reductase activity has been found associated with the MP virus isolated from the infected allantoic fluids or yolk sacs of fertile eggs and treated with trypsin, perfringens toxin, and cobra venom. The corresponding normal tissue enzymes can be nearly completely destroyed by such treatment, also the small activity found in crude preparations of influenza virus is destroyed by this treatment. Under certain relatively mild conditions of inactivation, loss in enzymatic activity is parallelled by loss in infectivity.
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PMID:Association of reduced diphosphopyridine nucleotide cytochrome c reductase activity with meningopneumonitis virus. 1342 22

Leptospira interrogans is a bacterium that is capable of infecting animals and humans, and its infection causes leptospirosis with a range of symptoms from flu-like to severe illness and death. Despite being a bacteria, Leptospira interrogans contains a plastidic class ferredoxin-NADP(H) reductase (FNR) with high catalytic efficiency, at difference from the bacterial class FNRs. These flavoenzymes catalyze the electron transfer between NADP(H) and ferredoxins or flavodoxins. The inclusion of a plastidic FNR in Leptospira metabolism and in its parasitic life cycle is not currently understood. Bioinformatic analyses of the available genomic and proteins sequences showed that the presence of this enzyme in nonphotosynthetic bacteria is restricted to the Leptospira genus and that a [4Fe-4S] ferredoxin (LB107) encoded by the Leptospira genome may be the natural substrate of the enzyme. Leptospira FNR (LepFNR) displayed high diaphorase activity using artificial acceptors and functioned as a ferric reductase. LepFNR displayed cytochrome c reductase activity with the Leptospira LB107 ferredoxin with an optimum at pH 6.5. Structural stability analysis demonstrates that LepFNR is one of the most stable FNRs analyzed to date. The persistence of a native folded LepFNR structure was detected in up to 6 M urea, a condition in which the enzyme retains 38% activity. In silico analysis indicates that the high LepFNR stability might be due to robust interactions between the FAD and the NADP(+) domains of the protein. The limited bacterial distribution of plastidic class FNRs and the biochemical and structural properties of LepFNR emphasize the uniqueness of this enzyme in the Leptospira metabolism. Our studies show that in L. interrogans a plastidic-type FNR exchanges electrons with a bacterial-type ferredoxin, process which has not been previously observed in nature.
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PMID:A highly stable plastidic-type ferredoxin-NADP(H) reductase in the pathogenic bacterium Leptospira interrogans. 2203 44