사과나무의 질산염환원효소

이희재 서울대학교 농업개발연구소 2000 농업생명과학연구 Vol.4 No.-

optimize the assay conditions for various tissues of MM 106 apple trees. Optimum co Factors affecting the in vivo nitrate reductase assay were investigated in order to ncentrations of nitrate and phosphate for in vivo nitrate reductase activities ranged from 50 to 100 mM and were tissue-specific. The optimum pH of the assay medium was 7.5. Vacuum infiltration and the addition of 2% (v/v) n-propanol to the assay medium resulted in stimulation of nitrate reducatase activity. The in vivo nitrate reductase assays for leaves and stems were linear for at least 60 minutes following an initial 30 minute lag, whereas there was no lag phase in root tissues. The effect of nitrate supply in the nutrient solution on nitrogen accumulation and nitrate reductase activity was examined. Increasing nitrate supply resulted in increases in the concentration and amount of reduced nitrogen in leaves and stems. The reduced nitrogen contents of trunk bark and trunk wood were significantly decreased when low nitrate was supplied, whereas that of roots was changed insignificantly. Most organs of MM 106 apple trees contained only a small portion of their total nitrogen as nitrate. The activity of nitrate reductase was measured using in vivo assay either with or without nitrate, namely in vivo+NO3 and in vivo- NO3 nitrate reductase assay. The in vivo- NO3 assay may be the better way to estimate reduced nitrogen accumulation than the in vivo+ NO3 assay. Increasing nitrate supply resulted in significant increases of in vivo- NO3 nitrate reductase activities of all organs. The proportion of leaf nitrate reductase activity to the total activity increased as the nitrate supply increased. The stems also contributed considerably to the total nitrate reducatase activity. Therefore, it can be concluded that nitrate reduction can occur in various parts of MM 106 apple trees as long as nitrate is available. Effect of darkness on intrate reduction was also examined in MM 106 apple leaves. As the period of darkness increased, nitrate reductase activity decreased and the accumulation of nitrate increased. The decrease in nitrate reductase activity with increasing period of darkness may be related to the decrease in soluble carbohydrates.

A Comparison of Wild and Cultivated Strawberries for Nitrogen Uptake and Reduction

Toktam Taghavi,Kevin M. Folta 한국원예학회 2014 Horticulture, Environment, and Biotechnology Vol.55 No.3

The strawberry (Fragaria × ananassa) requires substantial amounts of nitrogen to produce reasonable yields. Wild strawberries (e.g. F. virginiana) grow in soils in the absence of supplemental nitrogen and may possess desirablegenes, alleles or expression patterns that support efficient nitrogen uptake and assimilation. The F. virginiana accessionsand cultivated materials were used to monitor the accumulation kinetics of five nitrate responsive genes (nitrate transporter,NRT1.1; nitrate reductase, NIA1; nitrite reductase, NiR; ferredoxin NADP reductase, FNR; and transketolase, TK) alongwith nitrate reductase activity. The results revealed expression patterns that were reminiscent of those observed inArabidopsis. Wild strawberries exhibited higher transcript accumulation for all genes examined except the nitrate transporter,compared to cultivated materials. Nitrate reductase activity (NRA) did not change in roots but increased in leaves inresponse to nitrate. Most wild genotypes had higher NRA in aerial tissues compared to cultivated materials. Comparisons of enzyme activity to transcript accumulation kinetics suggest that available nitrate reductase is activatedand not likely synthesized de novo, suggesting that some wild accessions may possess enhanced nitrogen assimilationmechanisms. These attributes may be useful to breeding programs in the design of elite plants that may make moreefficient use of fertilizers.

암모늄태와 질산태 질소가 담배와 콩의 조직배양시 생육 및 질소대사 효소의 활성에 미치는 영향

박혜선,설종호,장매희 한국식물생명공학회 1998 식물생명공학회지 Vol. No.

Soybean and tobacco tissue cultured with modified MS media containing 4 different ratio(as N) of nitrate to ammonium combination which were 3:0, 2:1, 1:2 and 0:3. The highest callus growth in soybean were observed in the 2:1 medium. The medium containing nitrate only was detrimental to soybean callus growth. Tobacco callus grown with nitrate-only grew as well as those in the 2:1 and very slowly with ammonium-only. In tobacco callus, the total nitrogen in the callus increased with the increase of nitrogen concentration in the medium, but in soybean callus, the opposite result was noted. Nitrate reductase activity in tobacco callus was high when grown with nitrate-only but low with ammonium-only. In case of soybean callus, nitrate reductase activity was high in the 2:1 and remarkably low in nitrate-only medium. Both in soybean and tobacco callus, the activity of glutamine synthetase was high with nitrate-only, but low with ammonium. 본 실험은 질소원처리가 식물의 생육 및 질소대사에 미치는 영향을 규명하고자 조직배양을 실시하였으며 공시재료로는 담배 'NC 2326'와 대두 '단엽콩'을 사용하였다. 배지내 질소원의 종류와 그 비율을 달리했을 때 callus의 생육, 전 질소, 단백질 함량 그리고 nitrate reductase와 glutamine synthase의 활성 변화를 조사하였다. 단엽콩의 조직배양시 callus증식은 2:1처리구와 암모늄태 질소만 공급한 배지에서 높았던 반면 질산태만 공급한 경우 쉐는 callus증식이 저조하였다. 한편 담배는 질산태와 암모늄태 질소를 2:1로 혼용한 구가 callus증식이 좋았고, 암모늄태 질소단용구에서 저조하였으며, 질산태 질소단용구의 callus생육이 양호하였다. Callus내 전질소함량은 담배의 경우 배지내 질산태 질소가 많을수록 증가되어 질산태 질소단용구에서 가장 많았으며 암모늄태 질소단용구에서 가장 적었다. 한편 단엽콩은 이와 반대의 경향으로 암모늄태 질소단용구에서 가장 많았으며 질산태 질소단용구에서 가장 적었다. Callus의 nitrate reductase의 활성을 보면 담배는 질산태 질소단용구에서 활성이 높았으며 암모늄태 질소단용구에서 활성이 낮은 반면 단엽콩은 2:1 처리구에서 활성이 높았고 생육이 부진했던 질산태 질소단용구에서 현저하게 낮았다. Glutamine synthetase의 활성은 단엽콩, 담배 모두 질산태 질소단용구에서 활성이 높았으며 암모늄태 질소단용구에서 활성이 낮았다.

담배에서 질소 형태에 따른 흡수 양상 및 생육과 질소대사 효소의 활성 변화

李相珏,沈相仁,姜炳華,裵吉寬 韓國作物學會 1997 Korean journal of crop science Vol.42 No.5

질소의 형태를 질산태(NO3 -N), 암모니아태(NH4 +-N) 그리고 질산태와 암모니아태(NO3 -N + NH4 +-N)를 혼합한 양액 하에서 수경재배하여 담배의 생육단계별 질소이용에 따른 흡수 양상과 생육 및 nitrate reductase, glutamine synthetase 효소활성을 평가하여 질소 시비 유형에 따른 체내 질소대사의 기초자료를 제공하고져 축행한 결과는 다음과 같다. 질소의 형태별 생육은 NO3 -N, NH4 +-N 단독 처리구보다 혼합처리구에서 지상 및 지하부의 생육이 좋았고, NH4 +-N 처리구에서는 암모늄 독성에 의해 생육이 극히 불량하였다. 생육단계별 양액의 pH 변화는 NO3 -N 처리구에서 이식 초기부터 이식 후 40일까지 증가하였고 NH4 +-N 처리구에서는 이식 후 20일에 pH 3.42, 혼합처리구에서는 이식 후 30일에 pH 3.64까지 떨어졌다가 증가하였다. 혼합처리구의 질소흡수반응은 생육초기에서는 NH4 +-N의 흡수를 우선하고 생육중기부터 NO3 -N 흡수가 증가하여 흡수 양상을 달리하였다. 생육시기에 따라 흡수형태도 NO3 -N와 NH4 +-N 사이의 상대적인 비율에 의해 크게 영향을 미쳤다. 엽록소와 가용성 단백질은 혼합처리구에서 전질소는 NH4 +-N 처리구에서 높았고, 특히 NH4 +-N 질소를 시비하였을 때는 질소함량이 증가하였다. 질산함량이 증가하였다. 질산함량은 NO3 -N 처리구에서 암모니아함량은 NH4 +-N 처리구에서 높았고, 산소 활성은 혼합처리구에서 nitrate reductase와 glutamine synthetase 활성이 높았다. Tobacco plant was grown for 40 days hydroponically in nutrient solutions composed of different forms of nitrogen, like NO3 [-10] -N, NH4 + -N, and a mixed formulation of NO3 [-10] -N and NH4 + -N. Uptake response, nitrate reductase, and glutamine synthetase activity at growth stage were investigated to understand the basic knowledge of nitrogen metabolism. The better growth of shoot and root was observed in the mixed nutrient solution than NO3 [-10] -N or NH4 + -N, alone. The plant growth in NH4 + -N nutrient solution was poor due to ammonium toxicity. The pH of nutrient solution containing NO3 [-10] -N increased up to 40 days after transplanting. But the pH of solution containing NO3 [-10] -N decreased drastically to 3.42 at 20 days after transplant. The pH in the mixed formulation dropped to pH 3.64 at 30 days after transplant and showed re-increase. It is assumed that nitrogen of NH4 + -N form was taken up preferentially at early stage and NO3 [-10] -N form was taken up preferentially at middle stage in the treatment with the mixed solution. The result indicates that the relative proportion of nitrogen forms affected the uptake patterns at each growth stages. The contents of chlorophyll and soluble protein were high with the mixed solution. Total nitrogen content was the highest in NH4 + -N solution and the content also increased by the application of the mixed type of nitrogen. The amount of nitrate in leaves was high in NO3 [-10] -N treatment and the amount of ammonium was high in NH4 + -N treatment. The activity of nitrate reductase or glutamine synthetase was highest in the leaves grown in mixed nutrient solution than in those with any other single of nitrogen form.

The Changes of Nitrate/Nitrite Concentrations and Nitrate/Nitrite Reductase Activity Changes in Soil for the Development a HONO(nitrous acid) Model

Jeongsu KIM,Jungheon LEE 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

The aim of this study is to determine the activity of enzymes by soil microorganisms and to develop a HONO production model according to the change in nitrogen concentration in the soil. Most plants absorb nitrogen in the form of nitrate (NO₃⁻) after ammonium (NH₄⁺) is converted into NO₃⁻ by nitrifying bacteria. The NO₃⁻ is reduced to nitrite (NO₂⁻) by nitrate reductase, which is also reduced to NH₄⁺ by nitrite reductase. It is important for the development of HONO model to measure the concentration of a nitrogen source in the soil. Soil samples were collected from Jeollanam-do area. Quantitative analysis of NH₄⁺ was performed using the indophenol method. For quantitative analysis of NO₂⁻ and NO₃⁻, HPLC analysis at 214 nm (Sphereclone Sax column) was performed. The LOD and LOQ of NO₂⁻ and NO₃⁻ were lower than 0.1 ppm and 0.2 ppm, respectively. The concentration decreased with increasing soil depth. Soil samples from soybean fields had a reduced NO₃⁻ concentration from 111.60 ppm to 46.20 ppm. We plan to complete the HONO emission model by measuring the change in the nitrogen concentration and the activity of related enzymes in Korean soil and estimating the reaction rate constant.

Factors Affecting Nitrate Reductase Activity in Some Monocot and Dicot Species

Chanda, Sumitra V. 한국식물학회 2003 Journal of Plant Biology Vol.46 No.1

Activity of nitrate reductase (NR), the first enzyme in the nitrate-assimilation pathway, was estimated in the cotyledons of the sunflower (Helianthus annuus) using a standardized in-vivo method. Seedlings were grown in the light on a nitrate medium. Various factors that affect NR activity were optimized, including the molarity and pH of the reaction buffer, nitrate concentration, and use of a surfactant. We also determined whether NADH was required for nitrate reduction. The surfactant propanol (2%) gave the best results, and no NADH supplement was necessary. In a separate study, we compared the effect of various culturing components on in-vivo NR activity among monocot and dicot species, and found that Triton X-100 was the best surfactant for monocots whereas dicots performed better with n-propanol. Monocot species also required additional NADH as an external energy source. Moreover, specific purification procedures were needed to enhaned NR activity in dicotyledons. Finally, we also assessed the efficacy of in-vivo versus in-vitro procedures for assaying monocots versus dicots.

질소 시용수준에 따른 배 ‘신고’ 실생묘의 생육과 질소관련물질의 변화

金松南(Song Nan Jin),최동근(Dong Geun Choi),강인규(In Kyu Kang),한광수(Kwang Soo Han),최철(Cheol Choi) (사)한국생물환경조절학회 2006 시설원예‧식물공장 Vol.15 No.1

‘신고’ 실생을 대상으로 질소사용수준에 따른 생장 반응을 조사하고 질산환원효소 활성 측정을 통해 수체내에서의 질산 환원상태를 어느 정도 예측할 수 있는 지 알아보기 위하여 시험을 실시하였다. 사경시험에 사용한 영양액은 암모늄태와 질산태질소의 비율을 1:3으로 하고 질소농도를 100, 200, 400 및 600㎎ㆍL­¹의 4가지 수준으로 하였고, pH를 6.5로 조절한 후 포트당 3L씩 l일 3회 점적 관수를 실시하였다. 생육 중 수고와 건물중 모두 질소시용수준을 100과 200㎎ㆍL­¹로 하였을 때가 400과 600㎎ㆍL­¹에 비하여 유의하게 높고 무거웠으나 100과 200㎎ㆍL­¹의 처리간에는 큰 차이가 없었다. 질소의 시용수준이 600㎎ㆍL­¹일 때에는 질소 과잉 공급으로 신초 생장이 극히 불량하였다. 질 산태질소의 함량은 잎과 뿌리의 경우 조사시기에 따라 질소 시용 효과가 서로 다른 양상을 보였으나 줄기의 경우는 질소시용농도의 증기에 따라 증가하였다. 부위 별 전질소와 환원 질소의 함량은 처리 후 경우는 질소시용농도의 증가에 따라 증가하였다. 부위 별 전질소와 환원 질소의 함량은 처리 후 30일 경우 질소시용농도의 증가에 따라 증가하였으나 처리 후 60일과 90일에는 질소 시용 효과가 뚜렷하지 않았다. 기관별 in vivo(+NO₃?) NRA는 질소의 시용농도와 큰 관련이 없었으나 in vivo(-NO₃?) NRA는 뿌리를 제외한 잎과 줄기에서 질소시용농도의 증가에 따라 증가하는 경향이었다. 잎과 줄기의 in vivo(-NO₃?) NRA 분포는 질소의 시용농도 증가에 따라 증가하였으나 뿌리에서는 감소하였다. 배나무의 생장과 질산환원을 충분히 촉진할 수 있는 적정 질소농도는 200㎎ㆍL­¹이었다. This study was conducted to anticipate nitrate reduction state in tree through measurement of nitrate reductase activity (NRA) and investigate the effect of nitrogen concentrations (100, 200, 400, and 600 ㎎ㆍL­¹) on growth, the nitrogen content of various tissue, and NRA of pear (Pyrus pyrifolia cv. Niitaka) seedlings in sand culture. Nutrient solutions used in this experiment were adjusted to pH 6.5 and fixed the ratio of ammonium and nitrate to 1:3 and trickle-irrigated 3 times a day. Tree height and dry weight of various organs in seedlings were higher in low nitrogen concentration (100 and 200 ㎎ㆍL­¹) than in high nitrogen concentration (400 and 600 ㎎ㆍL­¹). The shoot growth in 600 ㎎ : L -I was extremely poor by nitrogen over supply. Increasing the nitrogen concentration, the concentration of nitrate-N in leaves and roots were insignificantly changed but that of stems increased. The accumulation of total and reduced nitrogen in all organs with increasing concentrations of nitrogen supply were increased at 30 days after treatment but those of all organs at 60 and 90 days after treatment were highest in 600 ㎎ㆍL­¹, whereas there were no significant changes among other nitrogen concentration. The in vivo (+NO₃?) NRA of all organs did not relate to nitrogen concentration but the in vivo (-NO₃?) NRA of leaves except roots increased with increasing the nitrogen concentration. Therefore, the proper nitrogen concentration to promote growth and nitrate reduction of pear tree was 200 ㎎ㆍL­¹.

The possible mechanisms involved in nanoparticles biosynthesis

H. Moteshafi,S.M. Mousavi,S.A. Shojaosadati 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.6

Several aspects of silver nanoparticle (NP) biosynthesis using Fusarium oxysporum under different conditions, that have not been previously considered, were explored. NP synthesis with different nitrate concentrations and silver sulfate instead of silver nitrate was investigated. The ability of F. oxysporum to synthesize NP under oxygen-limited conditions was also evaluated. In the presence of a nitrate reductase inhibitor, different mechanism rather than the reduction of metal ions by a nitrate-dependent reductase,was revealed. SDS-PAGE analysis indicated that a protein with 14 kDa molecular weight could be involved in a specific response of the fungus in the presence of silver ions.

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO₃<SUP>-</SUP>

Qiu-yan Yan,Zeng-qiang Duan,Jun-hui Li,Xun Li,Jin-long Dong 한국원예학회 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures (15°C, 20°C, and 25°C) within a natural aerial temperature (15-30°C). Four nitrate:ammonium (NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP>) ratios (10:0, 8:2, 5:5, and 2:8 mmol・L<SUP>-1</SUP>) at constant nitrogen (N) concentration of 10 mmol・L<SUP>-1</SUP> were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP> ratio in the 15°C solution, the 5:5 ratio in the 20°C solution and the 8:2 ratio in the 25°C solution. Photosynthetic rate (Pn) response to solution temperature and NO₃<SUP>-</SUP>:NH₄<SUP>+</SUP> ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

Cucumber Growth and Nitrogen Uptake as Affected by Solution Temperature and NO3-:NH4+ Ratios during the Seedling

Qiu-yan Yan,Zeng-qiang Duan,Jun-hui Li,Xun Li,Jin-long Dong 한국원예학회 2013 원예과학기술지 Vol.31 No.4

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth,photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures (15°C, 20°C, and 25°C) within a natural aerial temperature (15-30°C). Four nitrate:ammonium (NO3-:NH4+) ratios (10:0, 8:2, 5:5, and 2:8 mmol・L-1)at constant nitrogen (N) concentration of 10 mmol・L-1 were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area)in most N treatments. Dry weight accumulation was greatest at the 10:0 NO3-:NH4+ ratio in the 15°C solution,the 5:5 ratio in the 20°C solution and the 8:2 ratio in the 25°C solution. Photosynthetic rate (Pn) response to solution temperature and NO3-:NH4+ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.