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41.
Effect of exogenous ammonium on glutamine synthetase, glutamate synthase, and glutamate dehydrogenase in the root of rice seedling 总被引:1,自引:0,他引:1
Li Ze-song Zhang Chu-fu Lin Qing-hua Peng Jin Li Chang-jian He Guang-cun Peng Shao-bing John Bennett 《武汉大学学报:自然科学英文版》1999,4(3):358-362
Root biomass of rice seedlings was increased at lower concentration of exogenous NH
4
+
, but it was decreased at higher concentration of exogenous NH
4
+
. The level of free NH
4
+
in the roots was accumulated gradually with the increase of NH
4
+
concentration in the nutrient solution. The content of the soluble proteins was essentially constant at higher NH
4
+
. The activities of glutamine synthetase (GS), NADH-dependent glutamate synthase (NADH-GOGAT), and NADH-dependent glutamate
dehydrogenase (NADH-GDH) were risen with exogenous NH
4
+
concentration at the lower NH
4
+
concentration range. But the activities of GS and NADH-GOGAT were declined, and the level of NADH-GDH activity was kept constant
under higher NH
4
+
concentration. The GS/GDH ratio suggested that NH
4
+
was assimilated by GS-GOGAT cycle under lower NH
4
+
concentration, but NADH-GDH was more important for NH
4
+
assimilation and detoxifying NH
4
+
to the tissue cells at the higher NH
4
+
level. According to the growth and the activity changes of these ammonium-assimilating enzymes of rice seedling roots, 10.
0 μg/mL NH
4
+
-N in nutrient solution was more suitable to the rice growth.
Foundation item: Supported by the National Natural Science Foundation of China (No. 3987052), Natural Science Foundation of
Hubei Province and International Rice Research Institute, P.O. Box. 3217, 1271 Makati City, Philippines.
Biography: LI Ze-song(1968-), male, Graduate student. 相似文献
42.
电渗析法处理味精废水 总被引:3,自引:0,他引:3
用电渗析-BAR厌氧生物反应器对味精废水进行处理,结果表明,用电渗法能有效去除经预处理后的味精废水的氯离子,通过能耗和脱除率的综合比较,选定电渗析的隔离流速为3.4cm/s,当脱盐率大于70%(即ρ(Cl^-1)〈6g/L,每处理1t废水耗电约1.83kW.h,脱氯后的废水,用BAR厌氧生物反应器在中温(35℃)条件下处理,当反应器的CODcr容积负荷小于14kg/(m^3.d)时,CODcr的去除率可达90%以上。 相似文献
43.
44.
经硫酸铵盐析、DEAE-纤维素层析、苯-琼脂糖CL-4B(Phenyl-SepharoseOL-4B)层析和交联葡聚糖G-200(Sephadex G-200)层析等步骤从谷氨酸产生菌——黄色短杆菌中分离纯化的谷氨酸脱氢酶,酶活提高了230倍。该酶的分子量约为30万,由六个分子量约为5万的亚基组成,最适pH为8.9,并对热较稳定。在pH8.2时,以谷氨酸和NADP+为底物时的米氏常数值分别为0.294mol/L和0.1mmol/L。 相似文献
45.
用形态学的方法观察了尼莫地平和银杏叶提取物(含黄酮甙类24%和内酯3.4%)对谷氨酸神经毒性的影响。结果发现谷氨酸导致新生小鼠下丘脑弓状核变性、坏死,钙通道拮抗剂尼莫地平及血小板激活因子受体拮抗剂银杏叶提取物均可剂量依赖性地抑制谷氨酸引起的神经元损伤。结果提示钙离子超载及血小板激活因子的激活与谷氨酸的神经毒性作用有关 相似文献
46.
用多孔玻璃珠固定自制的谷氨酸氧化酶(GO)制成GO固定化酶管,并结合流动注射系统测定谷氨酸(Glu)的含量,测定的线性范围在0.2-3.0mol/m3,精密度(c.v.)为0.75%,测定速率每小时60个样品,该酶管使用寿命为40d,在一定的条件下,保存稳定期达120天,当测定的Glu浓度低于3mol/m3时,pH在6.5-7.5,温度在20-30度,磷酸盐浓度在0.05-0.25mol/L范围内变化时,对Glu含量的测定几乎无影响,用醋酸纤维膜修饰的铂电极测定H2O2选择性好,该方法与试剂盒法同时测定不同发酵时间发酵液中Glu的含量,两者结果一致。 相似文献
47.
Ø. Hvalby J. -C. Lacaille G. -Y. Hu P. Andersen 《Cellular and molecular life sciences : CMLS》1987,43(6):599-601
Summary Dendritic depolarization, which seems to be involved in the induction of long-term potentiation (LTP), was elicited by localized glutamate application. When paired to low frequency synaptic activation in the same area, the subsequent changes had features in common with LTP, expressed as an increased probability of firing and shorter spike latency. The EPSP was not significantly increased. 相似文献
48.
It is found for the first time that, after the structure and endocrine function of Hatschek’s pit ofBranchiostoma belcheri are damaged by monosodium glutamate (MSG) treatment in breeding season, the ovulation of mature ovary, as well as the development
of both ovary and testis of large-growth stage are obstructed and stagnated; and in non-breeding season, the process of gonadal
development is delayed. The disturbed ovulation and gonadal development can definitely be restored with exogenous gonadotropic
hormone as the therapeutical substitute. These results may provide new proof for the complete understanding of the evolutional
process of pituitary function in vertebrates and playing an important role in the reproductive endocrine control system of
Hatschek’s pit of amphioxus. 相似文献
49.
研究了树脂在味精脱色中的应用,比较6种树脂在脱色方面的性能,筛选出效果较好的树脂类型,并研究流速及温度对谷氨酸中和液脱色效果的影响,考察了D318树脂的再生性能.结果表明,D318树脂脱色效果最好,在实验条件下,最佳流速为0.02cm/s,温度为65℃。 相似文献
50.
银杏叶黄酮甙对谷氨酸神经毒性的保护作用 总被引:5,自引:1,他引:5
银杏叶的抽提物黄酮甙对许多疾病有重要的作用。本文研究了黄酮甙在体外是否改变神经元对兴奋性损伤的敏感性。当成热的大脑皮层细胞(来自小鼠)和海马细胞(来自人)经2.5μg/ml黄酮甙作用2天后,再用100μM谷氨酮处理5min,在形态学和生化性质上可见它们对谷氨酸的敏感性下降,提示黄酮甙可能是谷氨酸受体的拮抗物。 相似文献