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DNA fragments containing theKlebsiella oxytoca genes encoding -glucosidase and amylase were cloned into the kanamycin resistance transposon Tn5. Another DNA fragment containing two genes for polygalacturonatetrans-eliminase was cloned into Tn1721. These newly constructed transposons were then each transposed in vivo onto the broad-host-range plasmid pR751 and conjugally transferred to a variety of Gram-negative bacteria. These were then screened for the newly acquired phenotypes. 相似文献
3.
Enhanced recognition of a modified peptide antigen by cytotoxic T cells specific for influenza nucleoprotein 总被引:10,自引:0,他引:10
A previously identified Kd restricted epitope of influenza A virus nucleoprotein (147-161) was modified, resulting in recognition by Kd restricted cytotoxic T cells at significantly lower concentrations than the natural peptide sequence. This was achieved by first refining the epitope to the minimum determinant 147-158. Deletion of arginine 156 resulted in a peptide that was shown to be greatly superior in both dose response titrations and in its rate of association with cells to form targets. Analog peptides were tested to determine the important amino acid changes. These data suggest that T cell epitopes can be modified to result in improved immunological recognition. 相似文献
4.
Eugene M. Rinchik Terry Magnuson Bernadette Holdener-Kenny Gavin Kelsey Albert Bianchi Claudio J. Conti Fran?ois Chartier Kathryn A. Brown Stephen D. M. Brown Josephine Peters 《Mammalian genome》1992,3(Z1):S104-S120
Chair of Committee for Mouse Chromosome 7 相似文献
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Genetic and physical map of the 2,4-dichlorophenoxyacetic acid-degradative plasmid pJP4. 总被引:29,自引:12,他引:17 下载免费PDF全文
Plasmid pJP4 is an 80-kilobase, IncP1, broad-host-range conjugative plasmid of Alcaligenes eutrophus encoding resistance to mercuric chloride and phenyl mercury acetate and degradation of 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, and 3-chlorobenzoate. By the use of cloning, transposon mutagenesis, and restriction endonuclease analysis, a biophysical and genetic map of pJP4 was generated. 相似文献
7.
Plasmid pULB113 (RP4::Mini-Mu) promoted homologous gene transfer inAeromonas hydrophila; transfer of chromosomal markers occurred at frequencies of between 10–3 and 10–4 per donor cell regardless of the marker selected; this indicated chromosome transfer from multiple origins. With a variety of amino acid biosynthetic markers, a single circular map of this bacterium was constructed. 相似文献
8.
Abstract The determinants for a haemolysin from an extraintestinal isolate of Citrobacter freundii have been cloned and expressed in both Escherichia coli K12 and phylogenetically related bacteria. Compared with E. coli , where the haemolytic determinants are encoded in 7.5 kb, the hemolysin determinants of C. freundii are located on a 2.5-kb Hin dIII fragment in the recombinant plasmid PJP71. Chicken embryo tests indicate that this haemolysin does contribute to the pathogenicity of C. freundii . 相似文献
9.
Josephine E Hammond 《BMJ (Clinical research ed.)》1986,293(6543):393-394
10.
The Tel Hashomer variant of human G6PD migrates as two prominent components during electrophoresis in several gel systems in which red cell G6PD from other males migrates predominantly as a single band. Since human males normally have but one X-chromosome, the extra band of this variant seemed an exception to earlier biochemical and genetic observations suggesting that human red cell G6PD is determined by a locus on the X chromosome. Results of the present studies indicate that the Tel Hashomer variant is unusually susceptible to the formation of a complex which has a higher molecular weight than normal G6PD and which represents the slow electrophoretic component. The conditions of formation and disruption of this complex in crude and purified Tel Hashomer preparations suggest that it results from the formation of disulfide bridges between molecules of Tel Hashomer G6PD.Supported by U.S. Public Health Service Research Grants AM-11065 and FR-5406 and Research Career Development Award 5 K3 AM 7992. 相似文献