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1.
转马铃薯Y病毒复制酶基因烟草的获得及抗病性分析   总被引:4,自引:0,他引:4  
重组克隆DNA用KpnI/BamHI双酶切得到马铃薯Y病毒NIb基因,将其插入质粒pROK2相应切点中构成植物表达载体。用重组质粒pROK2转化农杆菌(Agrobacteriumtumefa-ciens)LBA4404菌株,叶盘法将NIb基因转入烤烟品种NC89的染色体,获得抗卡那霉素的转化再生植株。经抗性筛选、PCR检测、无性扩繁和大量重复抗病鉴定,结果表明,转化烟草植株DNA中整合了外源目的基因,且表现抵抗20μg/mlPVYN的侵染,ELISA分析认为抗性植株无病毒累积,初步筛选出对PVYN侵染具有较高抗性的转基因烟草植株。  相似文献   

2.
研究了黄色短杆菌生物合成L-异亮氨酸代谢控制途径,结果表明,选育L-异亮氨酸高产菌必须首先活化磷酸烯醇式丙酮酸羧化酶(PC)、天冬氨酸激酶(AK)、高丝氨酸脱氢酶(HD)、苏氨酸脱氢酶(TD)和乙酰羟基酸合成酶(AS)这五个关键酶,并减弱由丙酮酸激酶(PK)、柠檬酸合成酶(CS)、天冬氨酸β-脱羧酶(AD)、二羟吡啶二羟酸合成酶(PS)和高丝氨酸-O-转乙酰酶(HT)引起的五条分支代谢强度,从而强化生物合成L-异亮氨酸的主代谢流。根据这一育种思想,以黄色短杆菌(BrevibacteriumflavumATCC14067)为出发菌株,采用相关的氨基酸结构类似物进行定向育种,有目的地活化PC、AK、HD、TD和AS等酶,筛选获得的L-异亮氨酸高产菌ZQ-4,产酸达28~30g/L.  相似文献   

3.
FOREWORDFORPUBLICATIONDyeingandFinishingTechnology(DFT),thejournaloftheDyeingandFinishingSpecialityCommitteeofChineseSocietyo...  相似文献   

4.
福建省烟草仓贮害虫名录缨尾目THYSANURA衣鱼科Lepismatldae1.衣鱼CtenolepismavillosaFabricius分布:全省普遍发生。为害:夜间活动。常以碎烟末为食。鞘翅目COLEOPTERA窃蠹科Anobiidae2.烟草...  相似文献   

5.
利用已构建的含有短芽胞杆菌(Bacillusbrevis)和产气肠杆菌(Enterobacteraerogenes)、α -乙酰乳酸脱羧酶(α -acetolactatedecarboxylase,α -ALDC)基因的工程菌株 ,并使它们分别在大肠杆菌中高效表达 ,获得重组α -ALDC。在实验室 ,用2L体积的麦芽汁进行啤酒生产试验 ,添加2种重组α -ALDC后 ,使啤酒中的双乙酰含量快速下降到或始终保持在0.1mg/L以下。证明得到的重组α -ALDC能有效地降低啤酒中双乙酰含量。这2种重组α -ALDC可进一…  相似文献   

6.
发酵乳─最新研究动向(续)   总被引:1,自引:0,他引:1  
2.3 来自于乳酸菌最有应用价值的次生代谢产物2.3.1 天然抗菌物质  乳酸菌能产生许多抗菌物质,象nisin,diplocoxin,lactocillin,bacteriocin,acidophilin和bulgarin等。现已知道产生Nisin能力与质粒有关。大部分乳酸乳球菌菌种是由11种基因参与Nisin的合成,此11种基因称为NisinABTCIPRKFEG,而这些基因聚集在一个大的转座子上,其中nisA可转录出结构基因,而nisR可转录出一个反馈调节蛋白质,nisK可转录出一个组氨…  相似文献   

7.
THEUSEOFENZYMETOTRANSFORMSTARCHKapreliantsLUVelichkoTA(OdesaTechnologicalInstituteofFoodProductionNamedafterbyMVLomonosov,Ukr...  相似文献   

8.
细菌几丁质酶基因转化烟草的研究   总被引:1,自引:0,他引:1  
为了提高烤烟品种K 32 6对真菌病害的抗性 ,以烟草再生植株的叶片为受体 ,采用农杆菌介导法将细菌几丁质酶基因导入烟草 ,获得了抗卡那霉素的转化植株 ,经PCR检测 ,初步证明了细菌几丁质酶基因已整合到烟草的基因组中 ;同时研究了再生烟草叶片的耐卡那霉素水平、受体预培养对转化的影响以及促进转化植株的生根等。结果表明 :培养基中卡那霉素浓度为 5 0mg/L时 ,能完全抑制烟草叶片的再生 ;烟草叶片预培养 2d的转化率提高 ;添加 0 .2mg/LIAA(吲哚乙酸 )能显著地提高转化植株芽梢的生根率。  相似文献   

9.
TechniqueofSheepskinGarmentLeather特约栏目主持:肖传斌(德国司马化学有限公司上海办事处)垂询电话:(021)-64400682)1原材料材料:国产绵羊蓝湿皮厚度:0.8~1.0mm用料参照削匀皮重量 2水洗200% 水,35℃1.0% SUPRALAN 80(非离子型脱脂剂)0.1% 甲酸40分钟pH4.0排水3铬复鞣/中和100% 水,40℃1.5% PELGRASSOL SF(耐电解质合成加脂剂)1,5% PROVOL BA10分钟2.0% NOVALTAN…  相似文献   

10.
为了培育打顶后不长侧芽的烟草植株,通过同源克隆,在烟草(品种K326)中得到了与侧芽生长相关基因的1个片断,将该片段序列通过BLAST检索Genbank同源比对,发现该基因同番茄的LS基因有非常高的同源序列,另外与水稻的MOC基因、拟南芥的LAS基因也有一定的同源性,命名为TLR基因.将TLR基因阅读框内640 bp的正向和反向片断构建到RNAi载体pHANNIBAL内含子两侧,再经NotI酶切回收约4300 bp目的片段,并插入到双元载体质粒pART27中,成功构建了含TLR基因片段正反向重复序列的植物表达载体pHANNIB AL-TLR-P ART27.将pHANNIB AL-TLR-P ART27质粒导入根癌农杆菌LBA4404中并转化烟草叶片细胞,没有得到转基因再生植株,推测这与TLR基因表达被抑制有关.  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   

13.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

14.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

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This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

18.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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