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Acute intermittent porphyria caused by a C→T mutation that produces a stop codon in the porphobilinogen deaminase gene 总被引:5,自引:1,他引:4
G. A. Scobie D. H. Llewellyn A. J. Urquhart S. J. Smyth N. A. Kalsheker P. R. Harrison G. H. Elder 《Human genetics》1990,85(6):631-634
Summary A mutation of the porphobilinogen (PBG) deaminase gene that produces the cross-reacting immunological material (CRIM)-negative type of acute intermittent porphyria (AIP) has been identified in one of 43 unrelated patients with this form of the disorder. The mutation is a CT transition that abolishes a PstI recognition site in exon 9 of the gene and converts a codon for glutamine to a stop codon. 相似文献
3.
Varda Mann Ilana Ekstein Hilde Nissen Carrie Hiser Lee Mclntosh Joseph Hirschberg 《Plant molecular biology》1991,17(3):559-566
We have cloned and analyzed the sugar-beet mitochondrial gene for cytochrome oxidase subunit II (coxII). The sugar-beet and its deduced amino acid sequence were compared to its homologouscoxII gene sequences from both monocot and dicot plants. It was found to be highly conserved (89–95%) compared to homologue in other plant species. The 780 bp coding sequence of the sugar beetcoxII gene is interrupted at position 383 by a 1463 bp intron. This intron contains an additional 107 bp sequence that is not found in any of the plantcoxII genes studied thus far. The structure of the intron suggests that a large intron existed in an ancestralcoxII gene before monocots and dicots diverged in evolution. Three CGG codons in the sugar-beetcoxII coding sequence align with conserved tryptophan residues in the homologous gene of other species, suggesting that RNA editing takes place also in sugar-beet mitochondria. In 13 out of 24 codons ofcoxII mRNA that were found to be edited in four other plants, the sugar-beet gene already utilizes the edited codons. This phenomenon may indicate that the mitochondrial genome in sugar-beet is phylogenetically more archaic relative to these plants. An additional sequence of 279 bp that is identical to the first exon ofcoxII was identified in the mtDNA of the sugar-beet. This pseudo-gene is transcribed and its existence in the mitochondrial genome is unexplained. 相似文献
4.
FREE-FLOW ELECTROPHORETIC SEPARATION AND ELECTRICAL SURFACE PROPERTIES OF SUBCELLULAR PARTICLES FROM GUINEA PIG BRAIN
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![点击此处可从《The Journal of cell biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Continuous free-flow electrophoretic separation has been used to obtain relatively pure preparations of synaptosomes and synaptic vesicles from crude fractions of guinea pig brain homogenates. Measurements of the contents of protein, neuraminic acid, and bound acetylcholine; the activities of succinic dehydrogenase, adenosine triphosphatase, choline acetylase, and 5'-nucleotidase; and the uptake of 14C-labeled choline arid acetylcholine in the presence and absence of hemicholinium, all confirm the electron microscope evidence that the electrophoretic preparations are at least as pure as those obtained by ultracentrifugal methods. The electrophoretic mobility measurements have been used to calculate zeta potentials and surface charge densities for these particles. 相似文献
5.
An Improved Diluent for Rubella Hemagglutination and Hemagglutination-Inhibition Tests 总被引:3,自引:2,他引:1
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![点击此处可从《Applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Angela E. Auletta Gary L. Gitnick Carrie E. Whitmire John L. Sever 《Applied microbiology》1968,16(5):691-694
Rubella hemagglutinating (HA) antigen was prepared in BHK-21 tissue as 5% cell suspensions and from unconcentrated and 20× concentrated infected supernatant fluids. In some instances, unconcentrated fluids were treated with Tween 80 and ether; cell suspensions were treated with ether alone. Preparations were tested for HA activity in dextrose-gelatin-Veronal (DGV) buffer solutions; 0.85% NaCl; Sorenson's phosphate-buffered saline, pH 7.2; and a diluent of 0.9% NaCl, 0.1% CaCl2 (anhydrous), and 0.1% MgSO4·7H2O. HA titers were consistently two- to fourfold higher in the saline with added Ca++ and Mg++ than in DGV. Hemagglutination-inhibition titers of paired human sera were the same in either diluent. It is suggested that the interaction between rubella HA antigen and the red cells of young (less than 1-day-old) chicks may be at least partially ion dependent and that titers are enhanced by increased quantities of divalent cations. 相似文献
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Nonlegume hemoglobin genes retain organ-specific expression in heterologous transgenic plants. 总被引:3,自引:1,他引:2
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![点击此处可从《The Plant cell》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Hemoglobin genes from the nitrogen-fixing nonlegume Parasponia andersonii and the related non-nitrogen-fixing nonlegume Trema tomentosa have been isolated [Landsmann et al. (1986). Nature 324, 166-168; Bogusz et al. (1988). Nature 331, 178-180]. The promoters of these genes have been linked to a beta-glucuronidase reporter gene and introduced into both the nonlegume Nicotiana tabacum and the legume Lotus corniculatus. Both promoters directed root-specific expression in transgenic tobacco. When transgenic Lotus plants were nodulated by Rhizobium loti, both promoter constructs showed a high level of nodule-specific expression confined to the central bacteroid-containing portion of the nodule corresponding to the expression seen for the endogenous Lotus leghemoglobin gene. The T. tomentosa promoter was also expressed at a low level in the vascular tissue of the Lotus roots. The hemoglobin promoters from both nonlegumes, including the non-nodulating species, must contain conserved cis-acting DNA signals that are responsible for nodule-specific expression in legumes. We have identified sequence motifs postulated previously as the nodule-specific regulatory elements of the soybean leghemoglobin genes [Stougaard et al. (1987). EMBO J. 6, 3565-3569]. 相似文献
8.
Gregory M. L. Patterson Kathleen K. Baker Cynthia L. Baldwin Christine M. Bolis Faith R. Caplan Linda K. Larsen Ira A. Levine Richard E. Moore E. Moore Carrie S. Nelson Kathryn D. Tschappat Grace D. Tuang Michael R. Boyd John H. Cardellina Ralph P. Collins Kirk R. Gustafson Kenneth M. Snader Owen S. Weislow Ralph A. Lewin 《Journal of phycology》1993,29(1):125-130
Lipophilic and hydrophilic extracts from approximately 600 strains of cultured cyanophytes, representing some 300 species, were examined for antiviral activity against three pathogenic viruses. Approximately 10% of the cultures produced substances that caused significant reduction in cytopathic effect normally associated with viral infection. The screening program identified the order Chroococcales as commonly producing antiviral agents. 相似文献
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