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1.
黄嘌呤脱氢酶广泛分布在真核生物、细菌和古细菌中,是催化氧化嘌呤、蝶啶和醛类等多种杂环分子的氧化还原酶类,与氮同化、激素代谢、衰老的调控及活性氧产生等过程相关.耐辐射异常球菌(Deinococcus radiodurans R1)具有超强的氧化胁迫抗性和氧保护机制,其基因组含有完整的黄嘌呤脱氢酶编码基因xdhABC.为探...  相似文献   

2.
[目的]通过耐辐射异球菌(Deinococcus radiodurans)pprM基因可能功能的研究,为进一步开发利用耐辐射微生物宝贵基因资源奠定基础.[方法]通过PCR方法克隆pprM基因,利用穿梭表达载体pRADZ3将其转入大肠杆菌内,通过冲击试验分析其功能.[结果]pprM基因转入大肠杆菌,发现该基因能提高大肠杆菌的抗盐、耐旱能力.[结论]pprM基因是一个非常重要的抗逆基因,在农业育种方面有极好的应用前景.  相似文献   

3.
为提高油菜的盐胁迫的耐受性,文章以甘蓝型油菜(Brassica napus L.)下胚轴为转化材料,通过农杆菌介导法将耐辐射球菌(Deinococcus radiodurans,DR)的IrrE基因导入甘蓝型油菜84100-18(玻里马细胞质雄性不育恢复系)中,经过卡那霉素的筛选培养,获得了抗卡那霉素的再生植株,对抗性植株进行PCR和实时荧光定量PCR检测。结果表明:部分抗性植株多次重复检测显示为阳性植株,初步证实了IrrE已整合到油菜基因组中并且IrrE基因已经在这些植株中进行mRNA水平的转录。  相似文献   

4.
以优良玉米自交系综31的幼胚为受体材料,采用农杆菌介导法将来自微生物耐辐射奇球菌(Deinococcus radiodurans)的抗旱基因IrrE转入玉米幼胚组织细胞中,转化后的细胞通过抗性筛选,分化再生成苗。结果表明,经特异PCR检测,42株植株转入了IrrE基因,有29株收获种子。T_1代在温室大棚控制水肥试验及脯氨酸等生理生化指标检测表明,转基因植株具有良好的耐旱特性,为抗旱玉米新品种选育提供了较好的亲本材料。  相似文献   

5.
周惠  辛培尧  赵丽华  原晓龙  陈杰  周军 《安徽农业科学》2013,41(10):4255-4258,4267
[目的]分析重金属结合蛋白基因hmbp在转基因拟南芥中的功能。[方法]利用PCR方法从抗辐射奇异球菌(Deinococcus radiodurans)中克隆hmbp基因,并用沾花法转入拟南芥,用氯化镉处理得到的阳性植株后,检测转基因植株中的丙二醛、脯氨酸、可溶性糖、叶绿素含量、相对电导率及SOD、POD活性。[结果]与野生型相比,镉处理后的转基因拟南芥中脯氨酸、可溶性糖含量及SOD、POD活性增加较多,丙二醛含量增加较少,叶绿素含量减少较少。[结论]研究表明hmbp转基因拟南芥对镉具有很高的抗逆性。  相似文献   

6.
分析预测了耐辐射异常球菌(Deinococcus radiodurans)基因组中的一对双组份蛋白DtrA(DR_A0009)和DtrB(DR_A0010)。生物学软件分析结果显示,DtrA含有组氨酸激酶(HisKA_3)结构域和ATP酶(HATPase_c)结构域,且有4个跨膜区;DtrB含有接收结构域和HTH结构域,且有Lux家族的调控蛋白。两者共同构成一个转录单元。分别构建了dtrA和dtrB基因缺失突变株(ΔdtrA和ΔdtrB),发现42℃高温胁迫条件下,2个突变株的生长和生存率明显低于野生型菌株,而正常培养温度(30°C)条件下,突变株和野生型菌株的生长无差异。QRT\|PCR分析显示,dtrA或dtrB基因突变导致了热激相关基因发生下调。推测双组份蛋白DtrAB参与了耐辐射异常球菌在高温胁迫下的调控作用。  相似文献   

7.
利用PCR和体内同源重组技术,对耐辐射奇球菌(Deinococcus radiodurans R1)中光敏色素基因诱导缺失突变,构建了突变株bphP^-。对突变株分别进行不同剂量电离辐射(IR)和不同浓度过氧化氢(H2O2)处理,并以野生株R1做对照。结果表明:与野生株相比,突变株bphP^-对过氧化氢的敏感性明显上升,而对电离辐射的抗性野生型基本不变。不同性质的光照试验显示,强白光对野生菌株和光敏色素突变的耐辐射奇球菌都具有显著的抑制菌落生长作用,两者差异不明显。红光和蓝光对野生株和突变株的生长都没有明显的抑制作用。强白光照射对没有光敏色素调控体系的大肠杆菌K12菌株抑制不明显。因此,耐辐射奇球菌中光敏色素可能主要是作为氧化环境信号传递和调控的蛋白。  相似文献   

8.
耐辐射异常球菌(D. radiodurans R1)ktrA基因(DR_1666)编码的K+吸收蛋白在盐胁迫和渗透胁迫中起着重要作用。采用QRT\|PCR分析表明在盐和D\|山梨糖醇胁迫条件下,野生型菌株中ktrA基因表达均显著上调。同时采用融合PCR方法和同源重组技术,构建ktrA基因缺失突变株(ΔktrA),以野生型菌株DR做对照,分别用不同浓度的氯化钾和D\|山梨糖醇对突变株进行胁迫处理。结果显示,突变株ΔktrA对氯化钾和D\|山梨糖醇的敏感性明显高于野生型,表明ktrA基因在菌株耐受高盐和高渗透胁迫时起重要作用。该结果为深入研究D. radiodurans R1菌株中ktrA基因的功能提供了很好的基础。  相似文献   

9.
[Objective] This study aimed to characterize constituents of phosphorus(P)fractionation as well as reciprocities among factors in sediments of a freshwater shallow lake. [Method] Surface sediment was discretely sampled at 24 sites through Van Veen grabs. Based on a modified sequential extraction scheme, P fractionation was determined as Fe/Al bound P(Fe/Al-P), Ca bound P(Ca-P), solute and reductive P(S/R-P) and organic P(OP). Curve estimation and Pearson product-moment correlation were employed for statistical analysis. [Result] Total P(TP) content ranged from 443 to 774 mg/kg. Inorganic P(IP) was the major component of TP,of which Ca-P was dominated with an average of 51%±9.7%. Average contents of P fractionation were in the following order: Ca-P(51%) OP(29%) S/R-P(8%) Fe/Al-P(7%). The molar ratio of Fe to P was 11- 20, close to the threshold value of P leaching. [Conclusion] In freshwater shallow lakes, IP and Ca-P were prone to be relatively high, whereas Fe/Al-P was low compared with deep lakes. Occurrence of spatially monotonic gradient indicated the primary causation of anthropogenic sources. Imminent sediment P liberation was also expected. Close associations among TP, Fe/Al-P and Ca-P, implying that anthropogenic P was mainly bound to metals in particulates. Significant correlations of TOC and P fractionation highlighted endogenous mechanism and authigenic origin in sediments.  相似文献   

10.
油茶油脂的超临界CO_2萃取及效果研究   总被引:1,自引:0,他引:1  
对油茶油脂的超临界CO_2萃取工艺及其理化特性进行研究,据试验结果表明:油茶油脂的超临界CO_2最优提取条件为油茶籽仁过40目筛,萃取温度45℃,萃取压力35 MPa, CO_2萃取流速为35 L/h.超临界萃取油茶油脂酸值为0.73 mg/g(KOH),过氧化值为3.51 mmol/kg,碘价为88,色值为Y35, R1,达到国标GB 11765-2003规定的压榨一级油标准,其主要营养成份维生素E(201.5 mg/kg)、β-胡萝卜素(51.0 mg/kg)、角鲨烯(211.8 mg/kg)含量均要高于螺旋榨毛油中维生素E(182.9 mg/kg)、β-胡萝卜素(36.5 mg/kg)、角鲨烯(153.6 mg/kg)和石油醚浸提毛油中维生素E(191.4 mg/kg)、β-胡萝卜素(39.8 mg/kg)、角鲨烯(24.3 mg/kg)的含量.
Abstract:
Effects of extracting pressure, temperature, CO_2 flow rate and seed fineness on the extraction ef- ficiencies of the seed oil of Camellia oleif era Abel by supercritical CO_2 extraction and some physio-chemi-cal properties of the product were investigated. The optimized conditions for SFE were as follows: crashed oil-tea seed was sieved under 40 meshes and extracted at 45℃, under a pressure of 5 Mpa and with a CO_2 flow rate of 35 L/h. The crude SFE oil-tea camellia oil had an acidity value of 0.73 mg/g (KOH), a perox-ide value of 3.51 mmol/kg, an iodine value of 88 and a color value of Y=35 and R=1, being up to the re-quirements of top grade pressing oil-tea camellia seed oil in GB/T 11765-2003. The crude SFE oil contained more vitamin E(201.5 mg/kg),β-carotene(51.0 mg/kg) and squalene(211.8 mg/kg)than crude spiral ressing oil and organic extracted oil, whose vitamin E,β-carotene and squalene contents were 182.9 mg/kg, 36.5 mg/kg and 153.6 mg/kg and 191.4 mg/kg, 39.8 mg/kg and 24.3 mg/kg, respectively.  相似文献   

11.
Effect of Betaine on the Regulation of the Lipid Metabolism in Laying Hen   总被引:1,自引:0,他引:1  
The experiment was conducted to investigate the effects of betaine on lipid metabolism of laying hens. 1 600 ISA brown laying hens of 20 weeks of age were alloted randomly into 4 groups each with 4 replicates of 100 layers, the layers were given a corn-soybean basal diet with 0,400,600 and 800 mg/kg betaine respectirely. Results indicated that supplementation of 600 mg/kg betaine significantly improved lay performance, and increased egg production 8.67 % ( P < 0.04), decreased feed/egg ratio by 9.02 % ( P < 0.03) compared with control, but there were no significant differences in egg weight and feed intake. It was found that supplementation of 600 mg/kg betaine decreased weights of abdominal fat by 19.63 % (P < 0.02)and 22.35%(P<0.02), and decreased liver fat by 8.52%(P<0.05) and 16.28%(P<0.01) in 50 and 70 weeks of age respectively. Compared with control, in 70 weeks of age, activity of LPL in abdominal fat was decreased by 44.83% (P < 0.01), HSL activity in abdominal fat increased by 50.0% (P < 0.02), and MDH activity in liver was decreased by 28.74% (P<0.03). Supplementation of 600 betaine increased levels of T3 by 43.29%( P < 0.05) and 43.95 % ( P < 0.02) in 50 and 70 weeks of age respectively, and increased the concentration of cAMP in hypothalamus and anterior pituitary by 59.89% ( P < 0.01) and 24.03% ( P < 0.05) respectively in 70 weeks of age. The concentration of serum gluclose (GLU) , FFA and phospholipid were increased by 44.50% (P<0.03), 19.66%(P<0.03) and 71.66% (P<0.01) in 50 weeks of age. The concentration of serum gluclose (GLU), FFA and phospholipid were increased by 16.25% ( P < 0.05), 22.51% ( P < 0.02) and 22.42%(P<0.01) in 70 weeks of age.  相似文献   

12.
[Objective] The study aimed to lay a foundation for the further studies on function mechanism of NS1 protein in the interspecies transmission of waterfowl influenza virus. [Method] Using the serologic assay and the specific RT-PCR method, some strains of H9 subtype waterfowl influenza virus were isolated from the 12 to 20 day-old muscovy duck flocks without any clinical symptoms in different areas of Guangdong Province. Four of these strains, including A/duck/ZQ/303/2007(H9N2) (A3 for short), A/Duck/FJ/301/2007(H9N2) (C1 for short), A/Duck/NH/306/2007(H9N2) (D6 for short), A/duck/SS/402/2007(H9N2) (E2 for short), and a strain named A/duck/ZC/2007(H9N2) (L1 for short) from a muscovy duck died of avian influenza virus (AIV), were used for NS1 gene cloning and sequencing. Subsequently, the obtained NS1 gene sequences were compared with other NS1 sequences registered in GenBank, and the phylogenetic analysis was also conducted. [Result] When compared with the H9N2 AIV NS1 sequences in GenBank, the NS1 genes of the four AIV strains A3, C1, D6 and E2 displayed homologies ranging from 99% to 100% at nucleotide level, and 95% to 100% at amino acid level; while the NS1 gene of L1 strain displayed homology ranging from 94% to 97% at nucleotide level, and 93% to 98% at amino acid level. The phylogenetic tree demonstrated that A3, C1, D6 and E2 were highly resemblant, and L1 was closest to AY66473 (chicken, 2003). By comparison with the NS1 gene sequences of L1, AF523514 (duck), AY664743 (chicken) and EF155262.1 (quail) using DNAstar, A3, C1, D6 and E2 presented nucleotide variations at site 21(R→Q), 70, 71(KE→EG), 86 (A→S), 124 (V→M) and 225 (S→N), and amino acid variations at site 21, 70, 71 and 86 in dsRNA-dependent protein kinase (PKR) binding domain of NS1 gene, which induced the evident variations of antigenic determinant and surface probability plot of NS1 protein. [Conclusion] This study suggested that the amino acid sequence variation in PKR binding domain of NS1 protein had something to do with the virus pathogenicity.  相似文献   

13.
RP-HPLC法测定薏苡中薏苡素的含量   总被引:1,自引:0,他引:1  
采用HPLC法,以Diamonsil(R)C_(18)为色谱柱,乙睛-水(50∶50)为流动相,流速1 mL/min,柱温25℃,检测波长232 nm,建立了薏苡非种仁部位中薏苡素的高效液相含量测定方法.结果表明:薏苡素在0.096~1.92μg范围内呈良好的线性关系,该方法的平均回收率为99.12%(n=5),相对标准偏差(RSD)为0.89%,用此条件测得成都华西植物园中薏苡全草中薏苡素的含量为8.3078 mg/g.从成分薏苡素和资源综合利用的角度考虑,建议薏苡根、茎和叶可以入药.
Abstract:
To establish an RP-HPLC procedure for determining the content of coixol in the root,stem and leaf of Coixlacryma-jobi L.var.mayuen(Roman.) Stapf. Methods The Diamonsil(R)C_(18) col-umn was used with the mobile phase of acetonitrile-water (50: 50), a flow rate of 1 mL/min, a tempera-ture of 25℃and a wavelength of 232 nm. Results The linear range of coixol was 0.096-1.92μg. The av-erage recovery was 99.12% (n=5, RSD is 0.89 %). Coixol in the herbal of C. Lacryma-jobi L. Var. Mayue in the Botanical Garden of West China was 8.3078 mg/g. Conclusion This method proved to be simple, accurate,well replicable, and suitable for the determination of C.lacryma-jobi L.var.mayuen(Roman.) Stapf.  相似文献   

14.
Effects of low temperature and INA bacteria on the change of chlorophyll a fluorescence inyoung fruit from two apricot cultivars were investigated. Low temperature decreased the potential activity(Fv/Fo) ,conversion efficiency of primary light energy (Fv/Fm)of PS Ⅱ and photochemical quenching (qP) inyoung fruit of two apricot cultivars. Low temperature enhanced non-photochemical quenching qN, decreasingthe quantum yield of photosynthetic electron transfer. The presence of ice nucleating active (INA) bacteria in-tensified the effects of low temperature, raised the injury temperature threshold from - 4℃ to - 2 - - 3℃.INA bacteria can be a factor to induce frost susceptibility of apricot fruit. The amount of damaged PS Ⅱ activi-ty center was related to apricot fruit size and cultivar.  相似文献   

15.
[Objective] The preventive and therapeutic effects of Folium perillae extract(FPE)on hyperlipemia induced by feeding rabbit with high fat forage were observed.[Method] The high fat and cholesterol diet were adopted to create the hyperlipemia model of rabbit.The rabbits were randomly and equally divided into 5 groups which were NC(normal control)group,HLM(high lipid model)group,LFPE,MFPE and HFPE group(low,middle,high dosage of FPE were 0.17 g/kg,0.5 g/kg and 1.5 g/kg respectively).The contents of TC,TG,LDL-C,HDL-C,MDA and the activity of SOD in serum were detected respectively.[Result] The three FPE groups could decrease the contents of TC,TG,LDL-C,MDA significantly(P<0.01)compared with these of HLM group,and the contents of HDL-C(P<0.01))and the activity of SOD(P<0.05)in serum was increased significantly.[Conclusion] FPE could regulate blood-fat and counteract lipid peroxidation.  相似文献   

16.
[目的]研究不同供水量与施磷量对甘蔗经济性状的耦合效应.[方法]以广西甘蔗品种新台糖22号(ROC22)为材料,通过供水量设置3个水平,在甘蔗分蘖初期至伸长末期,每旬供水量分别为199.5m3/hm2(A1),400.5 m3/hm2(A2)、600.0 m3/hm2(A3);磷肥施用量设置4个水平,作为基肥分别施用P2O5 0 kg/hm2(B1)、120 kg/hm2(B2)、240 kg/hm2(B3)、360 kg/hm2(B4),来研究不同供水水平与磷肥水平组合处理对甘蔗产量和品质性状的影响.[结果]处理A2B2为较适合提高甘蔗经济性状的水磷配比处理.[结论]该研究结果为广西甘蔗生产中的水分、磷肥高效利用及甘蔗高产、高糖栽培提供理论依据. Abstract: [Objective] The aim was to study the coupling effect of water and phosphate on economic traits of sugarcane.[Method]Taking sugarcane variety ROC22 as tested material,coupling effects of different levels of water supply quantity and different levels of phosphorus fertilizer on the yield and quality of sugarcane were studied.Among them,water supply quantity had 3 levels,that was,the water supply quantity per 10 days from the early tillering stage of sugarcane to the end of elongation was 199.5 m3/hm2 (A1),400.5 m3/hm2 (A2) and 600.0 m3/hm2 (A3),respectively;Phosphorus fertilizer as basic fertilizer had 4 levels:P2O5 0 kg/hm2 (B1),120 kg/hm2 (B2),240 kg/hm2 (B3) and 360 kg/hm2(B4). [Result] Treatment A3B2 in water-fertilizer coupling was more suitable to improve economic traits of sugarcane. [Conclusion] The research results provide theoretical basis for the efficient utilization of water and phosphorus fertilizer in production of Guangxi sugarcane and the cultivation of high-yield and high-glucose sugarcane.  相似文献   

17.
A recombinant fowlpox virus co-expressing Haemagglutinin (HA) and Neuraminidase (NA)named as rFPV-HA-NA was produced by HA and NA gene of A/Goose/Guangdong/3/96 (H5NI)isolate of avian influenza virus recombined into the genome of fowlpox virus. In this study, to evaluate its ability of protecting chickens against challenge with a lethal dose of highly pathogenic isolates of avian influenza virus, eight-week-old specific-pathogenic-free (SPF) chickens were vaccinated with recombinant virus or the wildtype fowlpox virus by wing-web puncture. After challenge 4 weeks with i0 LD50 highly pathogenic avian influenza virus HSNI and H7NI isolate, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with the wildtype fowlpox virus or unvaccinated controls experienced 100% mortality respectively following challenge. This complete protection was accompanied by the high levels of specific antibody response to the respective components of the recombinant virus.  相似文献   

18.
在水相中低温条件下制备了巯基乙胺稳定的CdTe量子点(CdTe QDs).基于肝素钠(Heparin)对巯基乙胺稳定的CdTe QDs共振瑞利散射(RRS)的增强作用,同时二级散射(SOS)和倍频散射(FDS)也相应增强,建立了一种快速、简便、定量测定肝素的新方法,同时讨论了最佳反应条件和影响因素,以RRS为例,在311 nm处,RRS的光谱强度与肝素钠的质量浓度c/(I-I_0)有良好的线性关系(r=0.999 1),线性范围13.5~1000 ng/mL,检出限(3σ)为4.04 ng/mL.可用于血样中肝素钠的测定.
Abstract:
Aqueous cysteamine-capped CdTe quantum dots(QDs) were prepared under low temperature.A simple and rapid quantitative method for heparin determination was proposed, based on the fact that hepa-tin can enhance CdTe QDs resonance Rayleigh scattering (RRS) and the intensities of second-order scatter-ing (SOS) and frequency-doubling scattering (FDS).Factors affecting RRS for detecting heparin with cys-teamine-capped CdTe QDs were studied.At 311 nm, the RRS calibration plot of C/(I-I_0) with concen-tration of heparin was linear in the range of 13.5-1 000 ng/mL with a correlation coefficient of 0.999.The limit of detection (30) was 4.04 ng/mL.  相似文献   

19.
Potassium(K) and magnesium(Mg) levels and their balances are two factors affecting the growth of plant. However, the responses of different crop cultivars to K/Mg ratios are less clear. This study was aimed at assessing the different responses of tomato(Solanum Lycopersicum L.) cultivars to the different K/Mg supply ratios. Three tomato cultivars(Zhongza 9(ZZ), Gailiangmaofen(MF), and Jinpengchaoguan(JP)) were grown in pots with three different K~+/Mg~(2+) ratios(4:0, 4:1 and 8:1, represented by K/Mg_(4:0), K/Mg_(4:1), and K/Mg_(8:1), respectively). Compared with K/Mg_(4:1) treatment, the leaf chlorophyll content, net photosynthetic rate, and total biomass of tomato seedlings under K/Mg_(4:0) treatments were decreased by 69.7, 89.1, and 53.1%, respectively. The Mg deficiency symptoms were observed when the Mg content in shoot became lower than 4 mg g~(–1) DW. Compared with K/Mg_(4:1) treatment, total biomass of tomato seedlings of K/Mg_(8:1) treatment was decreased by 21.6%; the shoot and root Mg contents were decreased by 10.4 and 21.8%, respectively; and Mg uptake of tomato was reduced by 34.1%. There were significant differences in biomass and Mg uptake for the three cultivars between the different K~+/Mg~(2+) treatments. The Mg uptake of the three different cultivars ranked as ZZJPMF under Mg deficiency and high K condition. In conclusion, the growth and Mg uptake and allocation of tomato were influenced significantly by imbalance K and Mg supply. JP and ZZ were the cultivars with the highest efficiency in Mg uptake.  相似文献   

20.
[Objective] The paper was to explore the causes of phosphorus(P)efficiency of rice in Yunnan Province,and to provide strategy for ecological and environmental protection.[Method]Using 703 accessions of secondary core collections from 16 prefectures of five regions in Yunnan Province,two treatments of low available P(6.26mg/kg)versus normal P(available P 40mg/kg),and invalid P(available P 0.02 mg/kg)versus normal P(available P 70 mg/kg)were set,and zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P of rice landraces were investigated.[Result] Phosphorus efficiency and the activation characteristics of invalid P in soils from rice landraces of Yunnan Province had the similar identification indexes,viz.the relative indexes of four traits(tillering ability or effective panicle,root weight,biomass,and straw weight)could be the screening indexes of gene type of secondary core collection with phosphorus efficiency,which also reflected the zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P in soils of 16 prefectures among five regions.On the contrary,the relative panicle length,node length under panicle,leaf length,leaf width and plant height could only be the assistant indexes of identification for phosphorus efficiency.There were similar zonal characteristics between phosphorus efficiency and the activation characteristics of invalid P in soils of rice landraces in Yunnan Province.[Conclusion] The study had great importance to the conservation and utilization of biological diversity,which would make contribution to second green revolution of "less input,multiple output,promote health,and protect the environment".  相似文献   

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