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

There is a diurnal variation of nitrate reductase activity (NRA) measured in vivo in barley roots (Hordeum vulgare cv. Midas). In intact plants receiving a 16-hour photoperiod, NRA increases when the light is switched on, reaches a maximum value after 7 to 8 hours, and thereafter declines. Shoot removal (detopping) at the start of the photoperiod prevents the rise in NRA; detopping after 5 hours light leads to a rapid fall in NRA. The inclusion of 10 millimolar malate in the external medium causes a rise in NRA in plants detopped at the beginning of the photoperiod and thus seems to substitute partially for the illuminated shoot. Oxalate, fumarate, and tartrate did not have this effect. Preincubation of the roots of intact plants with 10 millimolar malate for 3 hours, prior to detopping, causes an increase in the flux of amino acids into the xylem sap of detopped roots.
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PMID:Effect of Shoot Removal and Malate on the Activity of Nitrate Reductase Assayed in Vivo in Barley Roots (Hordeum vulgare cv. Midas). 1666 Oct 28

The present study investigated nitrogen process in rhizosphere of Kandelia obovata under nitrogen input. Results showed that nitrogen additions significantly increased 4 kinds of enzyme activities (Urease, Nitrate reductase, Nitrite reductase and hydroxylamine reductase). The pH value increased to 7.1 under ammonium addition, but decreased to 6.9 under nitrate addition. Potential Nitrification Intensity (PNI) increased 200-1500% compared with control under ammonium addition, and Potential Denitrification Intensity (PDI) increased more than 200% under nitrate addition. Ten types of organic acids were detected from root exudates, which mainly included oxalic acid, tartaric acid, formic acid, acetic acid, and citric acid. The abundance of 5 kinds of microbial functional groups (nifH, AOA, AOB, nirS, nirK) responded differently. Total nitrogen in organs of K. obovata increased more than 200%. This indicated that nitrogen additions accelerated the transformation of nitrogen directly and stimulated the exudation of root exudates and 5 kinds of genes indirectly.
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PMID:Research on the nitrogen cycle in rhizosphere of Kandelia obovata under ammonium and nitrate addition. 2404 38