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61.
Metabolomics - A robust bioanalytical approach for the discovery of the modes-of-action of pesticides: A review 总被引:1,自引:0,他引:1
The agrochemical industry is facing great undertaking that includes increasing demand for the development of new crop protection agents that are safe for the environment and the consumers, and at the same time combat the issue of the emergence of resistance pest strains. The mode-of-action (MoA) is among the features of a bioactive compound that largely determine whether the abovementioned issues are addressed or not, and subsequently whether its commercial development will be addressed. The early discovery of the MoA of bioactive compounds could accelerate pesticide research and development by reducing the required time and costs. Based on advances in synthetic and natural product chemistry, scientists have access to a vast number of compounds that could potentially be developed as crop protection agents. The screening of such compounds with respect to their MoA requires accurate and robust bioanalytical tools. Metabolomics is a powerful bioanalytical tool that will likely play a significant role in the acceleration of the discovery of MoA of bioactive compounds. In the present review, the capabilities and principles and applications of metabolomics for the study of the MoA of herbicides, insecticides, acaricides, fungicides, and antibiotics are discussed. 相似文献
62.
63.
P. Stamp 《Journal of Agronomy and Crop Science》1988,160(3):183-190
A biochemical approach to maize breeding must be based on an exact knowledge about changes of relevant traits with ontogenetic stage. In 1983 seasonal patterns of net assimilation rate (NAR), chlorophyll and carotenoids contents, and of activities of RuBP carboxylase, PEP carboxylase and NADP malate dehydrogenase were recorded for two early maturing maize cultivars. For all traits the general trends were similar for both cultivars throughout the growing season but short term fluctuations were less synchronized after anthesis. About 75% of the maximum green leaf area was expanded within 20 days around middle of July. Specific seasonal patterns were observed for all traits. Before anthesis values were maximum for NAR in late June and in early July, for enzyme activities at the end of June and for pigment contents at the beginning of July. First decreases occurred for all traits before anthesis, further decreases were observed for PEP carboxylase in August and for chlorophyll content in September. Marked temporary declines coincided for NAR and pigment contents with a cold spell end of June and for these traits and RuBP carboxylase activity with anthesis. Evidence was scarce that any of the photosynthetic traits reflected the photosynthetic efficience of the two cultivars for a long stretch of time. 相似文献
64.
在相同条件下,对C_2植物中的9种双子叶植物和3种单子叶植物的核酮糖-1,5-二磷酸羧化酶/加氧酶(Rubisco)动力学特性进行了测定。K_m(CO_2)(K_c)和K_m(O_2)(K_(?))的变化范围分别为7.3~30μmol/L和300~1000μmol/L。变异系数分别为52%和38%。K_c值的变异明显高于K_o值。V_(max)(CO_2)(V_c)和V_(max)(O_2)(V_(?))分别为50~1500和16~500n mol/mg酶蛋白·min,变异系数相应为97%和87%。专一性因子的变化相对较小,为78~121,变异系数为15%。说明在C_3植物中,Rubisoo动力学特性的差异主要反应在V_(max)值上,核酮糖-1,5-二磷酸羧化酶(Rubisc)的动力学特性变化大于核酮糖-1,5-二磷酸加氧酶(Rubiso)。随着物种的进化,K_c、K_o值明显降低,而V_c、V_o值显著增加,致使Rubisco活性显著提高。Rubisco的羧化/加氧比也依物种的进化而上升。K_c与K_o、V_c与V_o之间具有显著的同步变化趋势,相关系数均超过极显著水平。 相似文献
65.
曹干 《福建农林大学学报(自然科学版)》1990,(1)
甘蔗不同基因型之间叶片 PEP 羧化酶的热稳定性有较大的差异。甘蔗叶片 PEP 羧化酶对高温敏感,在伸长盛期酶热稳定性相对较高;随着环境温度的下降,到伸长后期酶热稳定性明显变低,甘蔗叶片 NADP-苹果酸酶的热稳定性很高,不同基因型之间差异不大。显然,热逆境不会导致 NADP-苹果酸酶的严重失活而影响光合作用。 相似文献
66.
鉴定和获取了四种油料作物(油菜、大豆、花生和芝麻)中的细菌型PEPC基因,分析了所编码蛋白的保守结构域(BOX I-IV)和蛋白作用功能位点。基因包括甘蓝型油菜的Bna10093361、Bna1009749和Bna10093360,大豆的Glyma10g34970.1, Glyma01g22840.1和Glyma02g14500.1,芝麻的SIN1018296和花生的AhPPC5。这8个基因含有19~21个内含子,内部插入一个约350~600bp的高度变异区,编码的蛋白在C端形成R/KNTG结构域,在N端缺乏磷酸化作用位点。在种子发育的不同时期,油菜中仅Bna10093360表达,但其表达量不到油菜BnActin表达量的0.1%;大豆中Glyma10g34970.1表达量最高(接近大豆GlymaActin的2%),Glyma02g14500.1次之;花生AhPPC5表达量为花生AhActin的32%~175%,在种子不同发育时期表达量为早期>中期>晚期;芝麻SIN1018296表达量为芝麻SINActin的3%~18%,在种子发育时期的表达趋势和花生AhPPC5相似。8个基因种子中的表达模式差异明显,说明细菌型PEPC基因可能存在着广泛的功能分化。
相似文献
67.
In the present study, the effect of 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) on long-chain fatty acid oxidation by hepatocytes isolated from suckled neonatal pig liver (a low ketogenic and lipogenic tissue) was tested. Incubation of hepatocytes with AICAR (0.5 mM) in the presence of 1 mM of carnitine and 10 mM of glucose for 1 hour at 37°C had no significant effect on total [1-14C]-palmitate (0.5 mM) oxidation (14CO2 and 14C-Acid soluble products (ASP)). Consistent with the fatty acid oxidation, carnitine palmitoyltransferase I activity and inhibition of its activity by malonyl-CoA (10 μM) assayed in cell homogenate also remained constant. However, addition of AICAR to the hepatocytes decreased 14CO2 production by 18% compared to control (p < 0.06). The reduction of labeled carboxylic carbon accumulated in CO2 caused a significant difference in distribution of oxidative products between 14CO2 and 14C-ASP (p < 0.03) compared with the control. It was also noticed that acetyl-CoA carboxylase (ACC) was increased by AICAR (p < 0.03), indicating that ACC might drive acetyl-CoA toward fatty acid synthesis pathway and induce an increase in distribution of fatty acid carbon to 14C-ASP. Addition of insulin to hepatocyte incubations with AICAR did not change the oxidative product distribution between CO2 and ASP, but further promoted ACC activity. The increased ACC activity was 70% higher than in the control group when citrate was absent in the reaction medium and was 30% higher when citrate was present in the medium. Our results suggest that AICAR may affect the distribution of metabolic products from fatty acid oxidation by changing ACC activity in hepatocyte isolated from suckled neonatal piglets; however, the basis for the increase in ACC activity elicited by AICAR is not apparent. 相似文献
68.
石斛属植物具有兼性景天酸代谢植物特征,磷酸烯醇式丙酮酸羧化酶是该类植物碳代谢的关键酶。本研究选用3种石斛为材料,测定了其磷酸烯醇式丙酮酸羧化酶活性。结果表明,报春石斛晚间黑暗条件下酶活性较强,凌晨高达25μmolCO2/(m2·s),而在中午光照最充足时,酶的活性相对较弱;金钗石斛酶活性日变化特点与报春石斛相似,但是活性比较弱;鼓槌石斛的酶活性很弱,通常在8μmolCO2/(m2·s)以下,昼夜变化幅度很小,表现为黑暗状态下比光下更强。 相似文献
69.
重叠延伸PCR克隆拟南芥ACCase基因和植物表达载体构建 总被引:1,自引:0,他引:1
植物的乙酰辅酶A羧化酶(ACCase)催化乙酰辅酶A羧化生成丙二酸单酰辅酶A,是脂肪酸合成的第一步,该步骤是种子脂肪酸合成与含油量形成的关键调控步骤。拟南芥中的真核形式ACCase基因cDNA长约7,000bp,难以直接克隆。本研究先通过常规PCR将其cDNA分成八个重叠的片段分别扩增出来,再用重叠延伸PCR将得到的片段逐步拼接成长度为6890bp的完整的基因序列,测序证实克隆序列正确无误,最后将其克隆到农杆菌转化植物的载体上。序列分析发现ACCase基因的开放阅读框长度为6765bp,编码一个含2254个氨基酸残基的多肽链,推测其分子量约为250KDa。ACCase基因的成功克隆为利用该基因调控油料作物的含油量奠定了良好基础,同时为克隆长度较大的基因提供了一种经济可行的方法。 相似文献
70.
玉米PEPC 基因在籼型水稻保持系不同遗传背景下的效应及转PEPC基因后代的耐光氧化特性 总被引:2,自引:0,他引:2
分别以转PEPC Kitaake和Kitaake作父本,以4份不同来源的保持系珍汕97B、K17B、Ⅱ 32B和G2480B为母本构建F1,考查PEPC 的表达及其对光合性状和农艺性状的影响。导入PEPC 后,水稻净光合速率、气孔导度、胞间CO2浓度和PEPC酶活性均表现为增加,最突出的是其PEPC酶活性均成倍增加。蒸腾速率方面,只有K17B/PEPC 表现为下降。珍汕97B的净光合速率、气孔导度和PEPC酶活性一般配合力相对效应值均最大。在农艺性状上,G2480B/PEPC 的有效穗数、结实率和单株产量均大幅度提高,分别增加了31.46%、1.39倍和1.83倍,千粒重也增加了7.84%。珍汕97B/PEPC 由于穗变短,即使结实率和千粒重大幅度增加,减产仍达9.84%。G2480B的穗长、每穗粒数、结实率和单株产量一般配合力相对效应值均最大,而珍汕97B最小。在耐光氧化方面,转PEPC 基因Kitaake明显优于Kitaake。说明PEPC 单个基因对改善籼型三系保持系的光合性能和增加产量有较重要的作用。在供试的4份保持系中选用保持系宜考虑G2480B,PEPC 在此遗传背景下的表达丰度较高,提高结实率和单株产量等农艺性状的正效应最好。 相似文献