Nitrogen migration and transformation in the stormwater bioretention system were studied laboratory experiments, which effects of drying-rewetting particularly investigated. The occurrence distribution nitrogen plants, soil, pore water explored under different cycles. results clearly showed that could remove efficiently all incoming be retained topsoil (0–10 cm) accumulated planted layer. Howev...

A fluorescent labeling technique has been devised to quantitate dihydrofolate reductase levels in individual cells and has been used to examine the heterogeneity in dihydrofolate reductase levels within various populations of methotrexate-resistant and parental cells. Precise quantitation of cellular dihydrofolate reductase levels in parental and methotrexate-resistant cells (having up to sever...

Two versiconal hemiacetal acetate (VHA) reductase activities (designated I and II), which catalyzed the reaction from VHA to versiconol acetate (VOAc) during aflatoxin biosynthesis, were purified to apparent homogeneity from the cytosol fraction of the mycelia of Aspergillus parasiticus mutant NIAH-26 through the following chromatography steps: first, fractionation with ammonium sulfate and the...

Plants synthesize a great variety of isoprenoid products that are required not only for normal growth and development but also for their adaptive responses to environmental challenges. However, despite the remarkable diversity in the structure and function of plant isoprenoids, they all originate from a single metabolic precursor, mevalonic acid. The synthesis of mevalonic acid is catalysed by ...

BACKGROUND 5α-reductase activity might be important during the development of polycystic ovary syndrome (PCOS). However, the changes of 5α-reductase activity in PCOS subjects and the relationship between 5α-reductase activity and body mass index (BMI), insulin resistance (IR) remain largely unknown. METHODS We performed a meta-analysis to examine 5α-reductase activity in women with PCOS; expl...

Levels of nitrate reductase activity (EC 1.9.6.1.) as high as 11 mumoles nitrite produced/hour gram fresh weight were found in barley (Hordeum vulgare cv. Compana) roots grown under low oxygen conditions. Roots of plants given identical treatment under sterile conditions did not develop the high levels of nitrate reductase activity. The results suggest that the buildup of particulate, reduced v...

Methods were developed for determination of microsomal HMG-CoA reductase activity from freshly isolated human lymphocytes, monocytes, and granulocytes or cultured human lymphoid cells. Reductase activity in monocytes is approximately twice that in lymphocytes or granulocytes. The activity in cultured cells is approximately 34-fold greater than that in freshly isolated cells. Assay conditions we...

Synthesis and turnover of nitrate reductase molecules and soluble proteins of tobacco XD cells were studied by labeling pre-existing proteins with 14C-arginine to make them radioactive and with 99 atom % ‘5N to increase their buoyant density. The cells were then transferred to medium in which new proteins were synthesized from 14N and were radioactively labeled with 3H-arginine. The breakdown o...

3-Hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase is the major rate-limiting enzyme in sterol and non-sterol isoprenoid synthesis. Isoprenoids are involved in the mechanisms of cell proliferation and transformation leading notably to crucial post-translational maturation of small G-proteins of the Ras superfamily. HMG-CoA reductase is among the most highly regulated enzymes. It is controlled b...