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1.
It has been generally considered that the low productivity of Leguminosae is caused by accumulation in the reproductive organs of a large amount of protein and lipid, since the biochemical costs of synthesizing these compounds is higher than that for carbohydrate. However, we report here on results which show that: the growth efficiencies (dry matter accumulated/ (dry matter accumulated + respiration)) of reproductive organs of Gramineae and Leguminosae were similar; the growth efficiency of rice in the vegetative stage was greater than that of soybean and field bean, regardless of nitrogen application rate; and when 14CO2, 14C-sucrose or 14C-asparagine were introduced to the leaf at the maturation stage, respiratory loss of the introduced 14C was greater in soybean and field bean, especially in the light, than in rice. Thus, it is assumed that the low productivity in Leguminosae is caused by a larger respiratory loss under both dark and light condition in the shoot, and not in the reproductive organs. 相似文献
2.
Kazuo Fukushima Goh Hooi Gnoh Sakae Shinano 《Bioscience, biotechnology, and biochemistry》2013,77(10):1495-1502
Cathepsin D was isolated from crude extract of chicken muscle by the purification procedures of acid- and heat-treatments, ammonium sulfate fractionation, DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration. The enzyme was purified about 3700 fold and homogeneous in disc-electrophoretic analysis. The molecular weight was found to be about 36,000 and the isoelectric point to be pH 7.3. The best substrate for this enzyme was 6 m urea-denatured casein, and its activity was maximal at pH 3.5 and 40°C. This enzyme was most stable between pH 4 and 5, and its stability was affected by cupric ion. The enzyme activity was markedly inhibited by sodium laurylsulfate and oxidizing agents such as potassium permanganate, N-bromosuccinimide and iodine, and was slightly activated by hydrogen peroxide. The purified cathepsin D was found to be fairly similar to the acid protease from lotus seed, previously reported by the authors. 相似文献
3.
Ontogenetic changes of rates of photon-saturated photosynthesis (P
sat) and dark respiration (R
D) of individual leaves were examined in relation to nitrogen content (Nc) in rice, winter wheat, maize, soybean, field bean, tomato, potato, and beet. P
sat was positively correlated with Nc as follows: P
sat = CfNc + P
sat0, where Cf and P
sat0 are coefficients. The value of Cf was high in maize, medium in rice and soybean, and low in field bean, potato, tomato, and beet, of which difference was not explained by ribulose-1,5-bisphoshate carboxylase/oxygenase (RuBPCO) content. R
D was explained by P
sat and/or Nc, however, two models must be applied according to plant species. R
D related linearly with P
sat and Nc in maize, field bean, and potato as follows: R
D = a P
sat + b, or R
D = aNc + b, where a, a, b and b are coefficients. In other species, the R
D/P
sat ratio increased exponentially with the decrease of Nc as follows: R
D/P
sat = a exp(b Nc), where a and b are coefficients. Therefore, R
D in these crops was expressed as follows: In(R
D) = ln(a P
sat) + b Nc, indicating that R
D in these crops was regulated by both P
sat and Nc. 相似文献
4.
Transcriptomic analysis indicates putative metabolic changes caused by manipulation of phosphorus availability in rice leaves 总被引:10,自引:0,他引:10
5.
6.
Ishikawa Junko Fujimura Shigeto Kondo Motohiko Murai-Hatano Mari Goto Akitoshi Shinano Takuro 《Plant and Soil》2018,424(1-2):503-524
Plant and Soil - In the Mediterranean basin, reduction in cloudiness owing to climate change is expected to enhance solar ultraviolet (UV) levels and to decrease rainfall over the coming years,... 相似文献
7.
LjMOT1, a high‐affinity molybdate transporter from Lotus japonicus,is essential for molybdate uptake,but not for the delivery to nodules 下载免费PDF全文
Guilan Duan Tsuneo Hakoyama Takehiro Kamiya Hiroki Miwa Fabien Lombardo Shusei Sato Satoshi Tabata Zheng Chen Toshihiro Watanabe Takuro Shinano Toru Fujiwara 《The Plant journal : for cell and molecular biology》2017,90(6):1108-1119
Molybdenum (Mo) is an essential nutrient for plants, and is required for nitrogenase activity of legumes. However, the pathways of Mo uptake from soils and then delivery to the nodules have not been characterized in legumes. In this study, we characterized a high‐affinity Mo transporter (LjMOT1) from Lotus japonicus. Mo concentrations in an ethyl methanesulfonate–mutagenized line (ljmot1) decreased by 70–95% compared with wild‐type (WT). By comparing the DNA sequences of four AtMOT1 homologs between mutant and WT lines, one point mutation was found in LjMOT1, which altered Trp292 to a stop codon; no mutation was found in the other homologous genes. The phenotype of Mo concentrations in F2 progeny from ljmot1 and WT crosses were associated with genotypes of LjMOT1. Introduction of endogenous LjMOT1 to ljmot1 restored Mo accumulation to approximately 60–70% of the WT. Yeast expressing LjMOT1 exhibited high Mo uptake activity, and the Km was 182 nm . LjMOT1 was expressed mainly in roots, and its expression was not affected by Mo supply or rhizobium inoculation. Although Mo accumulation in the nodules of ljmot1 was significantly lower than that of WT, it was still high enough for normal nodulation and nitrogenase activity, even for cotyledons‐removed ljmot1 plants grown under low Mo conditions, in this case the plant growth was significantly inhibited by Mo deficiency. Our results suggest that LjMOT1 is an essential Mo transporter in L. japonicus for Mo uptake from the soil and growth, but is not for Mo delivery to the nodules. 相似文献
8.
A protease from the lotus seed (Nelumbo nucifera Gaertn) was purified by acid-treatment, ammonium sulfate-fractionation, ethylalcohol-fractionation, TEAE-cellulose-treatment and Sephadex G-100 gel-filtration.The enzyme was purified about 870-fold and was homogeneous in electrophoretic and ultracentrifugal analyses.Purified lotus seed protease is an acid protease with a pH optimum at 3.8 toward urea-denatured casein. It is active for casein and hemoglobin. But other proteins such as edestin, zein, lotus seed globulin and soybean casein are slightly hydrolyzed and egg albumin is hardly hydrolyzed. This enzyme is most stable at pH 4.0 below 40°C. The enzyme is not a thiol protease, and its activity was completely inhibited by potassium permanganate, remarkably inhibited by sodium dodecylsulfate and accelerated by hydrogen peroxide. 相似文献
9.
Noureddine Benkeblia Takuro Shinano Mitsuru Osaki 《Metabolomics : Official journal of the Metabolomic Society》2007,3(3):297-305
In the present study, non-aqueous fractionation (NAQF) and GC-MS were used to obtain a spatially resolved view of metabolism
in mature leaves of soybean (Glycine
max Merr.). NAQF of lyophilized soybean leaves was performed using CCl4-n-heptane and ultracentrifugation that yielded a gradient comprised of six fractions. Chlorophyll content, and marker enzyme
activities, phosphoenolpyruvate carboxylase (PEPC) and α-mannosidase, were utilized as stroma, cytosol and vacuole markers,
respectively. GC-MS analyses of each fraction resulted in the identification of around 100 different metabolites. The distribution
of these identified compounds showed a decreasing order from the vacuole to cytosol to chloroplast stroma. In other words,
a greater number of identified compounds were found in the vacuole when compared to the cytosol or stroma.
Levels of sugars, organic acids and fatty acids showed greater relative abundances in the vacuole with 50, 55, and 50% of
the respective pools. A greater relative abundance of amino acids was observed in the cytosol where 45% of the total of amino
acids content was recorded. The relatively large pool of sugars and phenolic acids in the vacuole compartment implies high
levels of starch metabolism and phenylpropanoid biosynthesis. The low amino acids pool, on the other hand, suggests low nitrogen
accumulation in the leaves of soybean. Hierarchical cluster analysis on the most abundant metabolites revealed three clusters
containing 10, 20, and 2 of the 32 selected metabolites. The data were discussed in term of NAQF and GC-MS analysis of soybean
mature leaves, and also in term of distribution and compartmentation of metabolites at subcellular levels. 相似文献
10.
mRNA expression patterns of genes for metabolic key enzymes sucrose phosphate synthase (SPS), phosphoenolpyruvate carboxylase (PEPC), pyruvate kinase, ribulose 1,5-bisphosphate carboxylase/oxygenase, glutamine synthetase 1, and
glutamine synthetase 2 were investigated in leaves of rice plants grown at two nitrogen (N) supplies (N0.5, N3.0). The relative gene expression patterns were similar in all leaves except for 9th leaf, in which mRNA levels were generally depressed. Though increased N supply prolonged the expression period of each mRNA,
it did not affect the relative expression intensity of any mRNA in a given leaf. SPS Vmax, SPS limiting and PEPC activities, and carbon flow were examined. The ratio between PEPC activity and SPS Vmax was higher in leaves developed at the vegetative growth stage (vegetative leaves: 5th and 7th leaves) than in leaves developed after the ear primordia formation stage (reproductive leaves: 9th and flag leaves). PEPC activity and SPS Vmax decreased with declining leaf N content. After using 14CO2 the 14C photosynthate distribution in the amino acid fraction was higher in vegetative than in reproductive leaves when compared
for the same leaf N status. Thus, at high PEPC/SPS activities ratio, more 14C photosynthate was distributed to the amino acid pool, whereas at higher SPS activity more 14C was channelled into the saccharide fraction. Thus, leaf ontogeny was an important factor controlling photosynthate distribution
to the N- or C-pool, respectively, regardless of the leaf N status. 相似文献