Nitrate reductase activity in chosen mosses: a case of study in skalny colliery waste tip / Aktywność reduktazy azotanowej u wybranych mchów na przykładzie hałdy powęglowej skalny

Abstract Two species of mosses in relation to nitrogen metabolism were examined. This subject is little known in this group of plant. Investigations of nitrate reductase activity in green tissues of Brachythecium rutabulum (Hedw.) Schimp. and Atrichum undulatum (Hedw.) P.Beauv. were performed. The study was conducted in two localities: heavy contaminated waste tip Skalny located in Upper Silesia, and Blonia City Park in Bielsko-Biala which place was chosen as a control area. For both species high activity of the enzyme was detected. The nitrate reductase activity varied between 99 to 9093 nmol per g dry mass per hour for B. rutabulum and 265 to 5135 nmol per g d.m. per hour of nitrite synthesized for A. undulatum respectively on Skalny waste tip. In the control area the results varied between 747 to 1077 for B. rutabulum and 171 to 518 nmol per g d.m. per hour of nitrite synthesized for A. undulatum, respectively. The differences were statistically significant only between the two species but not between habitats probably due to high dispersion and small amount of replications. The levels of nitrate and nitrite in stream water in both areas were also measured. In the Skalny waste tip there were high and reached 1.66 mg · dm-3 of nitrite and 65 mg · dm-3 of nitrate, respectively. In the control area these amounts were lower and reach zero level for nitrite and 4.5 mg · dm-3 of nitrate, respectively.

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Pre-Sowing Irrigation Plus Surface Fertilization Improves Morpho-Physiological Traits and Sustaining Water-Nitrogen Productivity of Cotton

Agronomy ◽

10.3390/agronomy9110772 ◽

2019 ◽

Vol 9 (11) ◽

pp. 772

Author(s):

Zongkui Chen ◽

Hongyun Gao ◽

Fei Hou ◽

Aziz Khan ◽

Honghai Luo

Keyword(s):

Nitrate Reductase ◽

Root Growth ◽

Root Length ◽

Crop Production ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Soil Layer ◽

Dry Mass ◽

Cotton Production ◽

Nitrogen Productivity

The changing climatic conditions are causing erratic rains and frequent episodes of moisture stress; these impose a great challenge to cotton productivity by negatively affecting plant physiological, biochemical and molecular processes. This situation requires an efficient management of water-nutrient to achieve optimal crop production. Wise use of water-nutrient in cotton production and improved water use-efficiency may help to produce more crop per drop. We hypothesized that the application of nitrogen into deep soil layers can improve water-nitrogen productivity by promoting root growth and functional attributes of cotton crop. To test this hypothesis, a two-year pot experiment under field conditions was conducted to explore the effects of two irrigation levels (i.e., pre-sowing irrigation (W80) and no pre-sowing irrigation (W0)) combined with different fertilization methods (i.e., surface application (F10) and deep application (F30)) on soil water content, soil available nitrogen, roots morpho-physiological attributes, dry mass and water-nitrogen productivity of cotton. W80 treatment increased root length by 3.1%–17.5% in the 0–40 cm soil layer compared with W0. W80 had 11.3%–52.9% higher root nitrate reductase activity in the 10–30 cm soil layer and 18.8%–67.9% in the 60–80 cm soil layer compared with W0. The W80F10 resulted in 4.3%–44.1% greater root nitrate reductase activity compared with other treatments in the 0–30 cm soil layer at 54–84 days after emergence. Water-nitrogen productivity was positively associated with dry mass, water consumption, root length and root nitrate reductase activity. Our data highlighted that pre-sowing irrigation coupled with basal surface fertilization is a promising option in terms of improved cotton root growth. Functioning in the surface soil profile led to a higher reproductive organ biomass production and water-nitrogen productivity.

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Role of narK2X and narGHJI inHypoxic Upregulation of Nitrate Reduction byMycobacteriumtuberculosis

Journal of Bacteriology ◽

10.1128/jb.185.24.7247-7256.2003 ◽

2003 ◽

Vol 185 (24) ◽

pp. 7247-7256 ◽

Cited By ~ 122

Author(s):

Charles D. Sohaskey ◽

Lawrence G. Wayne

Keyword(s):

Nitrate Reductase ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Anaerobic Growth ◽

Reporter System ◽

Whole Cells ◽

Hypoxic Conditions ◽

Cell Extracts ◽

Insertional Inactivation ◽

Nitrate And Nitrite

ABSTRACT Mycobacterium tuberculosis is one of the strongest reducers of nitrate in the genus Mycobacterium. Under microaerobic conditions, whole cells exhibit upregulation of activity, producing approximately eightfold more nitrite than those of aerobic cultures of the same age. Assays of cell extracts from aerobic cultures and hypoxic cultures yielded comparable nitrate reductase activities. Mycobacterium bovis produced only low levels of nitrite, and this activity was not induced by hypoxia. M. tuberculosis has two sets of genes, narGHJI and narX of the narK2X operon, that exhibit some degree of homology to prokaryotic dissimilatory nitrate reductases. Each of these were knocked out by insertional inactivation. The narG mutant showed no nitrate reductase activity in whole culture or in cell-free assays, while the narX mutant showed wild-type levels in both assays. A knockout of the putative nitrite transporter narK2 gene produced a strain that had aerobic levels of nitrate reductase activity but failed to show hypoxic upregulation. Insertion of the M. tuberculosis narGHJI into a nitrate reductase Escherichia coli mutant allowed anaerobic growth in the presence of nitrate. Under aerobic and hypoxic conditions, transcription of narGHJI was constitutive, while the narK2X operon was induced under hypoxia, as measured with a lacZ reporter system and by quantitative real-time reverse PCR. This indicates that nitrate reductase activity in M. tuberculosis is due to the narGHJI locus with no detectable contribution from narX and that the hypoxic upregulation of activity is associated with the induction of the nitrate and nitrite transport gene narK2.

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Salivary Nitrate, Nitrite and Nitrate Reductase Activity in Relation to Risk of Oral Cancer in Egypt

Disease Markers ◽

10.1155/1998/507653 ◽

1998 ◽

Vol 14 (2) ◽

pp. 91-97 ◽

Cited By ~ 24

Author(s):

Alaa F. Badawi ◽

Gehan Hosny ◽

Mohamed El-Hadary ◽

Mostafa H. Mostafa

Keyword(s):

Oral Cancer ◽

Nitrate Reductase ◽

Odds Ratio ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Healthy Individuals ◽

Oral Cancer Patients ◽

Nitrate And Nitrite ◽

Increased Activity

It has been suggested that nitrate and nitrite may play a role in the etiology of human oral cancer. We investigated whether salivary nitrate and nitrite and the activity of nitrate reductase (NRase) may affect the risk of oral cancer in Egypt, an area with high levels of environmental nitrosating agents. Levels of salivary nitrite (8.3 ± 1.0 μg/ml) and nitrate (44 ± 3.7 μg/ml) and activity of NRase (74 ± 10 nmol/ml/min) were significantly (P< 0.05) higher in oral cancer patients (n= 42) compared to control Egyptian healthy individuals (n= 40, nitrite = 5.3 ± 0.3 μg/ml, nitrate = 27 ± 1.2 μg/ml, and NRase activity = 46 ± 4 nmol/ml/min). The adjusted odds ratio (OR) and the 95% confidence intervals (C.I.) for risk of oral cancer, categorized by the levels of salivary nitrate and nitrite and NRase activity, showed a higher cancer risk associated with nitrite > 7.5 μg/ml (OR: 3.0, C.I.: 1.0–9.3), nitrite > 40 μg/ml (OR: 4.3, C.I.: 1.4–13.3) and NRase activity > 50 nmol/ml/min (OR: 2.9, C.I.: 1.1–7.4). Our findings suggest that increased consumption of dietary nitrate and nitrite is associated with elevated levels of salivary nitrite. Together with the increased activity of salivary NRase, these observations may explain, at least in part, the role of nitrate and nitrite in the development of oral cancer in individuals from an area with a high burden ofN-nitroso precursors.

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Changes in Nitrate Reductase Activity and Contents of Nitrate and Nitrite During Cold Hardening and Dehardening of Crowns of Winter Wheat ( Triticum aestivum L.) 1

Crop Science ◽

10.2135/cropsci1964.0011183x000400040005x ◽

1964 ◽

Vol 4 (4) ◽

pp. 356-359 ◽

Cited By ~ 2

Author(s):

Frank R. Toman ◽

A. W. Pauli

Keyword(s):

Triticum Aestivum ◽

Nitrate Reductase ◽

Winter Wheat ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Triticum Aestivum L ◽

Cold Hardening ◽

Nitrate And Nitrite

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Nitrate reductase activity and yield of dry mass and protein content in cucumber seedlings supplied with nitrates and ammonium

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1979.037 ◽

2015 ◽

Vol 48 (3) ◽

pp. 465-471 ◽

Cited By ~ 3

Author(s):

J. Buczek ◽

M. Burzyński

Keyword(s):

Nitrate Reductase ◽

Protein Content ◽

Nutrient Solution ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Sole Source ◽

Dry Mass ◽

Inhibitory Effect ◽

Cucumber Seedlings ◽

Nr Activity

The presence of NH4+ ions in a nutrient solution containing NH4NO3 with the K+ ions removed, caused an inhibition of nitrate reductase (NR) activity in cucumber leaves. The lack of K+ in a NaNO3 medium also decreased the NR activity. Addition of K+ to these media suppressed the inhibitory effect of NH4+ and enhanced the NR activity in the leaves of plants growing in NaNO3 nutrient solution. The results suggest that K+ is essential for NO3- reduction, Na+ is less effective in this process, whereas NH4+ ions markedly inhibit NO3- reduction. The protein content and increment of dry mass of cucumber plants grown 10 days with NH4-N as the sole source of nitrogen was significantly lower as compared with NO3-N supplied plants feed with plants feed with both forms of mineral nitrogen (NH4NO3). The results show that cucumber prefers the nitrates, although it can utilize the ammonium form of nitrogen.

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Effect of tungsten on nitrate and nitrite reductases in Azospirillum brasilense Sp7

Canadian Journal of Microbiology ◽

10.1139/m91-128 ◽

1991 ◽

Vol 37 (10) ◽

pp. 744-750 ◽

Cited By ~ 9

Author(s):

Christian Chauret ◽

Roger Knowles

Keyword(s):

Nitrate Reductase ◽

Nitrite Reductase ◽

Azospirillum Brasilense ◽

Nitrate Reductase Activity ◽

Paracoccus Denitrificans ◽

Reductase Activity ◽

Whole Cells ◽

Azospirillum Brasilense Sp7 ◽

Nitrite Reductase Activity ◽

Nitrate And Nitrite

Tungstate, at concentrations that completely suppressed nitrate reductase activity in Paracoccus denitrificans, caused only partial inhibition of nitrate reductase in Azospirillum brasilense Sp7. Nitrate reductase activity in cell-free extracts was much more sensitive than whole cells to tungstate, suggesting that there may be a barrier to its transport. Nitrite reductase activity was partially inhibited by tungstate in both whole cells and cell-free extracts. Azospirillum brasilense apparently scavenged enough contaminating molybdenum from molybdenum-limited medium to allow maximum nitrate reductase activity, which was not stimulated by added molybdate. Cells grown in molybdenum-depleted medium could not reduce nitrate. Nitrate concentrations less than 0.25 mM inhibited activity, but not synthesis, of nitrite reductase and caused significant accumulation of nitrite during reduction of nitrate. Key words: Azospirillum brasilense, Paracoccus denitrificans, nitrate reductase, nitrite reductase, tungsten, molybdenum, denitrification.

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Effect of copper on the dynamics of the increment of plant dry mass and on some physiological processes in sunflower (Helianthus annuus L.)

Acta Agrobotanica ◽

10.5586/aa.1983.001 ◽

2013 ◽

Vol 36 (1-2) ◽

pp. 5-16

Author(s):

U. Wojcieska ◽

E. Wolska ◽

M. Ruszkowska

Keyword(s):

Nitrate Reductase ◽

Helianthus Annuus ◽

Chlorophyll Content ◽

Nitrate Reductase Activity ◽

Reductase Activity ◽

Vegetation Period ◽

Dry Mass ◽

Mineral Elements ◽

Growth And Yield ◽

Effect Of Copper

Experiments were undertaken in order to establish the influence of copper on the growth and yield of plants. Sunflower (Helianthus annuus L.) was grown in pots with peat enriched with mineral elements with the excluding of Cu. Copper was applied immediately after plant germination in doses of 0, 5 and 125 mg Cu per pot. In the form of CuSO4. During the vegetation period the following determinations were made: (a) dynamics of the increase of plant dry matter and of the assimilative surface, (b) chlorophyll content, (c) nitrate reductase activity and (d) intensity of photosynthesis and photosynthetic activity. The results indicate that copper deficit restricts the process of photosynthesis and the dynamics of dry mass increment. Differences in copper dosage did not have an immediate influence on the chlorophyll content and nitrate reductase activity, only rather an intermediate effect through the influence on the process of ageing.

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