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101.
非同位素PCR-单链构象多态性技术的建立和应用 总被引:2,自引:0,他引:2
PCR-单链构象多态性技术问世以来,成为研究基因突变的工具,特别是在分子肿瘤学研究中,广泛应用于癌基因,抑癌基因突变的研究,常规PCR-SSCP采用同位素标记PCR产物,测序板电泳分离突变,在操作和费用上有种种局限,文章建立了一种非同位素PCR-SSCP技术;通过不对称PCR获得单链,普通PAGE分离,经银染检出突变,用这种方法,还研究了四株鼻咽癌细胞株CNE1,CNE2,HK1和SUNE1中肿瘤 相似文献
102.
Summary Plant hairy root cultures of Lithospermum erythrorhizon were carried out to produce shikonin derivatives by employing in situ extraction with n-hexadecane in a shake flask and a bubble column bioreactor. Over 95 % shikonin produced was recovered in the n-hexadecane layer. In flask cultures the maximum concentration of shikonin with n-hexadecane extraction was 3 times higher than that obtained without extraction. In the two phase bubble column reactor, 572.6 mg/L of shikonin and 15.6 g/L of dry cell mass were obtained after 54 days. Shikonin was produced at a constant level of 10.6 mg/L day during this period. 相似文献
103.
Phillip E. Klebba Jeanette M. Rutz Jun Liu Christopher K. Murphy 《Journal of bioenergetics and biomembranes》1993,25(6):603-611
The recent solution of enteric bacterial porin structure, and new insights into the mechanism by which outer membrane receptor proteins recognize and internalize specific ligands, advocates the re-evaluation of TonB-dependent transport physiology. In this minireview we discuss the potential structural features of siderophore receptors and TonB, and use this analysis to evaluate both existing and new models of energy and signal transduction from the inner membrane to the outer membrane of gram-negative bacteria. 相似文献
104.
The structure of the predicted amino acid sequence in the FX domain of Photosystem 1 was studied by molecular modeling and a working hypothesis was developed for the functional interaction of PsaC with the core heterodimer. We propose that the intervening sequences between homologous cysteines in the FX cluster form two flexible loops and participate in the binding of PsaC, and that the arginine residues in the two surface-exposed loops may promote the interaction between the P700–FX core and the subunit. The model was tested experimentally; chemical modification of arginine residues in the P700–FX core using phenylglyoxal prevented reconstitution of the core with PsaC and PsaD after insertion of FeS clusters in vitro. Treatment of the P700–FX core with trypsin also prevented reconstitution of terminal electron transfer to FAFB, although neither treatments affected the electron transfer to FX as judged by flash kinetic spectrophotometry. Electron transfer in the P700–FAFB complex was not impaired by either phenylglyoxal or trypsin treatment indicating that the small subunit(s) protect the arginine residues that become chemically modified or cleaved. The data are consistent with the working model and point to additional experiments designed to identify the specific residues involved in the interaction between the P700–FX core and PsaC.Abbreviations PG-
phenylglyoxal
- PS 1-
Photosystem 1 相似文献
105.
106.
107.
魏建军 陈丙玺 杨亚萍 蔡富强 郭亦寿WEI Jian-Jun CHEN Bing-Xi YANG Ya-Ping CAI Fu-Qiang GUO Yi-Shou 《遗传》1993,15(2):33-35
RFLP(限制性片段长度多态)技术应用于遗传病的诊断始于1981年。在十年时间里,这一基因诊断技术和分析方法不断得到发展和改进。随着越来越多的致病基因和连锁DNA多态片段的分离和克隆,该技术在分析缺陷基因性质,携带者检出和产前诊断等方面将发挥重要作用.然而,RFLP技术复杂,耗费时间和费用较大,使其向临床推广应用面临很大局限性。因此,基因诊断的方法简化和技术改进大有必要。1985年首创的多聚酶链 相似文献
108.
Hatanaka Shin-Ichi Furukawa Jun Aoki Toshio Akatsuka Hirokazu Nagasawa Eiji 《Mycoscience》1994,35(4):391-394
Combining different chromatography systems, unusual nonprotein amino acids were isolated and unequivocally identified from a small amount (less than 100 g fresh weight) ofAmanita gymnopus fruit body. Without obtaining crystals of these amino acids, on the basis of1H-NMR determination, high resolution mass spectrometry, chlorine analysis and oxidation with L-amino acid oxidase, one of them proved to be a new chloroamino acid, (2S)-2-amino-5-chloro-4-hydroxy-5-hexenoic acid (G2). The other three were (2S)-2-amino-5-hexenoic acid (G1), (2S)-2-amino-4,5-hexadienoic acid (G3) and (2S)-2-amino-5-hexynoic acid (G4). Amino acid (G1) was also encountered for the first time in natural products. Amino acid (G3) has been reported from several kinds of fungi belonging toAmanita, subgenusLepidella. The occurrence of amino acid (G4) was already reported fromCortinarius claricolor.Part 23 in the series Biochemical studies of nitrogen compounds in fungi. Part 22, Hatanaka, S. I. et al. 1985. Trans. Mycol. Soc. Japan26: 61–68. 相似文献
109.
渍水对冬小麦生长的危害及其生理效应 总被引:7,自引:0,他引:7
吕军 《植物生理与分子生物学学报》1994,(3)
小麦受渍后叶片的光合和蒸腾速率迅速下降,而后则显微弱的回升趋势。渍害不仅削弱小麦光合产物的积累,并且改变光合产物在地上部分和根系中的分配比例;植株根/冠比下降,而黄叶的发展与根/冠比的变化呈显著负相关;渍害改变小麦的发育进程,尤其是后期渍害明显促使小麦早衰。认为清水使叶片光合速率降低、光合有效面积损失和衰老加速,从而危害小麦的生长。 相似文献
110.
为了将外源基因导入花椰菜原生质体获得转基因植株,本文研究了PEG介导的外源基因在花椰菜下胚轴原生质体中的瞬间表达。(1)20%PEG将质粒pBI221导入原生质体后GUS表达比13%PEG导入的高,但易造成原生质体损伤。(2)热激处理增强表达,但在随后的培养过程中易造成原生质体降解。(3)原生质体状况对表达有重要影响,5d龄下胚轴原生质体比8d龄的表达强。(4)不同质粒及启动子表达强度不同。质粒pKIWI101比pBI221表达强3倍左右。 相似文献