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141.
水稻白叶枯病菌对拌种灵抗药性分子机制研究 总被引:4,自引:0,他引:4
通过紫外诱变获得了抗拌种灵水稻白叶枯病菌(Xanthomonas oryzae pv.oryzae)的突变体,这些突变体可以在含100 μg·ml-1拌种灵平板上生长,而敏感菌株在10 μg·ml-1浓度下则不能生长。敏感菌株琥珀酸脱氢酶活性受拌种灵强烈抑制,而抗药突变体的酶活性较低,且不受药剂抑制。应用6对引物,从水稻白叶枯病菌野生敏感菌株和室内诱导抗药性菌株中扩增到琥珀酸脱氢酶基因全序列。该基因全长3 616 bp,编码1 115个氨基酸,含有2个内含子。与柑橘溃疡病菌(Xanthomonas axonopodis pv. citri)琥珀酸脱氢酶核苷酸同源性93%,氨基酸同源性97%;与其它6种病原细菌琥珀酸脱氢酶基因编码的氨基酸序列同源性为43%~95%。敏感菌株和抗药菌株的琥珀酸脱氢酶序列分析表明,琥珀酸脱氢酶铁硫蛋白亚基中229位氨基酸由组氨酸(CAC)突变为酪氨酸(TAC)是导致X. oryzae对拌种灵产生抗药性的主要原因。 相似文献
142.
143.
Seshadri Shivashankar Manoharan Sumathi Vala Keshava Rao 《The Journal of Horticultural Science and Biotechnology》2017,92(2):113-119
Uneven ripening (UR) is a physiological disorder of unknown origin in ‘Bangalore blue’ grape (Vitis vinifera × Vitis labrusca) leading to wine of inferior quality. A preliminary study found wide variations in total dehydrogenase activity (TDH) of seeds from unevenly ripe berries. In our experiments, gibberellin (GA3) applied to young grapes increased seed TDH activity and reduced the incidence of uneven ripening to 2% compared with 35% in the control. In contrast, paclobutrazol (PBZ) decreased TDH activity and increased the incidence of the disorder to 58%. GA3-treated berries had higher concentrations of sucrose and TDH activity in seed representing mature seeds with high viability. In contrast, PBZ-treated and control berries had higher concentrations of glucose and lower TDH activity, indicating immature seeds with low viability. These results suggested that competition among developing berries can lead to differences in seed gibberellin content, seed viability and the rate of berry growth resulting in green, purple, and black berries at harvest. The study established the role of seed viability in uneven ripening and demonstrated that the incidence of the disorder is reduced by the application of GA3 to immature berries. 相似文献
144.
AIM: To investigate the effect of garlicin on mouse viral myocarditis and to explore the possible mechanisms. METHODS: Forty BALB/c mice were randomly divided into 4 groups: control group, viral myocarditis group, low-dose garlicin group and high-dose garlicin group. The morphological changes of the myocardium were observed with HE staining. The levels of lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and creatine kinase (CK) were measured by colorimetric method. The protein levels of Bcl-2, Bax, cleaved-caspase-9, cleaved-caspase-3, cleaved-PARP and cleaved-caspase-8 in the myocardial tissues were determined by Western blot. RESULTS: The morphological observation with HE staining showed that garlicin inhibited the necrosis of the myocardium and infiltration of inflammatory cells. Compared with viral myocarditis group, garlicin dose-dependently decreased the levels of LDL, AST and CK. Moreover, garlicin treatment decreased the protein levels of Bax, cleaved-caspase-9, cleaved-caspase-3 and cleaved-PARP, accompanied with an increase in Bcl-2 expression. However, garlicin had no effect on the protein level of cleaved-caspase-8. CONCLUSION: Garlicin effectively attenuates the myocardial damage in mice with viral myocarditis through inhibition of intrinsic apoptosis pathway. 相似文献
145.
三角叶滨藜甜菜碱醛脱氢酶基因克隆及植物表达载体的构建 总被引:2,自引:1,他引:2
通过RT PCR技术从盐生植物三角叶滨藜总RNA中,扩增并克隆了BADH68基因。该基因全序列显示,核苷酸序列长1520bp,12~1515bp为1个开放阅读框架,推测的氨基酸序列全长为500个氨基酸残基,其核苷酸序列与菠菜和山菠菜同源性分别为89%和95%。利用BamHI和SacI酶切位点将BADH68基因连接到pCAMBI A2301的多克隆位点,并把35S启动子和nos终止子分别连接到BADH基因的上游和下游的多克隆位点上,获重组植物表达质粒pCAMATBADH682,并转入根癌农杆菌LBA4404中,获LBA4404(pCBAMATBADH682)菌种。 相似文献
146.
Accordilgtothemoleculargenehcs,thekeyOfbiodiversitywassequenceofal1tinoacidsinPrOtelnwhosegenehclnformahonwerestoredinDNA.Inl958,CrickPOsedthefamouscentraldogmaandthesequencehy-POthesisandalsofOrcastedaPpearaceofthe.lll.Proteintaxonomy.InthefOllowing3Oyears,lotsofProteinswerepuredandsequenced.Thecomparisonofhomologenousproteinse-quencesfromvanousorganismsshowedthattheclosertwOsPecieswere,themoresimilarsequencesofawhnoacidswere,oronthecon-trary.ResearchesbasedonfossilsbycomparingsubshtU… 相似文献
147.
《Journal of Crop Improvement》2013,27(2):349-361
Summary In vitro effects of purified alfalfa (Medicago sativa L.) saponins (soyasaponin I, medicagenic acid [MA-3,28Na], MA-3glu, 28Na, and MA-3,28glu) on rhizosphere bacteria cell suspensions were investigated. Triphenyltetrazolium chloride (TTC)-dehydrogenase and fluorescein diacetate (FDA) hydrolytic activities were strongly inhibited (90-95%) by MA-3,28Na and MA-3glu,28Na in Bacillus thurin-giensis strains (HD-2 and UZ404). In Curtobacterium flacumafaciens (JM1011), TTC and FDA activities were reduced only by MA-3,28Na, while little or no effects were observed on the gram-negative strains Pseudomonas fluorescens (RA-2) and Agrobacterium tumefaciens (A-136). Soyasaponin I decreased FDA hydrolysis in HD-2 and JM1011, but increased FDA activity by 2-fold in RA-2. MA-3glu,28Na increased protein exudation or leakage by 5 to 10-fold in all strains, and MA increased leakage in all strains except RA-2. Soyasaponin increased protein leakage about 2-fold in JM1011, RA-2 and A-136, but reduced extracellular protein in HD-2 and UZ404. Results suggest that MA-3glu,28Na can deleteriously affect rhizobacteria, and in most cases, the aglycone (MA-3,28Na) is as biologically active as the sapo-nin MA-3glu,28Na. 相似文献
148.
稻瘟病菌3—磷酸甘油醛脱氢酶基因的克隆及序列分析 总被引:3,自引:0,他引:3
以PCR为基础结合cDNA库构建,分两段克隆稻瘟病菌的3-磷酸甘油醛脱氢酶基因(gpd)分别测序,合并,获得该基因编码区全部1011bp的核苷酸序列,可以编码336个氨基酸和1个终止密码子TAA。该序列与其它12种丝状真菌的已知gpd基因序列有着高度的同源性,它们的核苷酸序列同源性为61.4%~86.6%,氨基酸序列同源性为64.6%~86.3%,尤其在酶活性功能区,不同丝状真菌间有着近100T 相似文献
149.
为了明确转cry1Ac基因抗虫棉对土壤酶活性的影响,本研究采集转cry1Ac基因抗虫棉及其亲本棉‘SM 3’种植地的土壤,测定转cry1Ac基因抗虫棉及其亲本棉 ‘SM 3’不同生育期内根区距主根不同距离土壤脱氢酶、脲酶和磷酸酶活性的变化。结果表明,棉花根区土壤脱氢酶活性在整个生育期呈现出先升高后降低再升高的变化趋势,土壤脲酶和磷酸酶活性在整个生育期无明显的起伏变化。转基因棉‘GK 12’盛花期和枯死期根区5 cm的土壤脱氢酶活性显著高于亲本棉‘SM 3’(p<0.05),转基因棉‘GK 12’盛花期根区15 cm和25 cm的土壤脱氢酶活性也显著高于亲本棉‘SM 3’(p<0.05);在棉花蕾期,转基因棉‘GK 12’根区5 cm和15 cm的土壤磷酸酶活性显著高于亲本棉‘SM 3’(p<0.05),而对根区25 cm的土壤磷酸酶活性无显著影响(p>0.05);转基因棉‘GK 12’在整个生育期对不同距离土壤脲酶活性无显著影响(p>0.05)。上述结果初步看出,在棉花生长的一些生育时期,转cry1Ac基因抗虫棉‘GK 12’对根区土壤酶活性存在明显的影响,但其影响的程度不是很大,后期基本可得到恢复。 相似文献
150.
Cronic exposure to an increased temperature (e.g., 10 °C as compared to 5 °C) and to a different oxygen tension can dramatically affect muscle cellularity in Atlantic salmon embryos at a developmental stage close to hatching. Maximal activities of enzymes of aerobic and anaerobic metabolism have been shown to vary with temperature and growth rates in fish but only limited data are available for embryonic fish. In order to obtain data on Atlantic salmon embryos and to be able to compare temperature and oxygen effects, the maximal activities of lactate dehydrogenase (LDH) and cytochrome c oxidase (CCO) were determined in body tissue containing mainly muscle as measures of anaerobic and aerobic metabolism, respectively. Temperatures of 5 and 10 °C, different O2 tensions (50% normoxic, normoxic, 150% normoxic), and growth within (chorionated) or without (dechorionated) the egg capsule were chosen as environmental conditions. Temperature affected CCO activities and thus the CCO/LDH ratio in dechorionated but not in chorionated embryos (5 < 10 °C) and had no effect on LDH activities. However, changes in oxygen availability had an effect on all parameters measured. Tissue protein concentration increased after dechorionation but no temperature effect was found. Both LDH and CCO activities undergo complex responses to oxygen availability depending on incubation temperature. There thus appeared to be an interaction of temperature and oxygen availability with regard to maximum activities of key enzymes of the aerobic and anaerobic metabolism in the salmon embryos. 相似文献