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Endosymbiotic origin and codon bias of the nuclear gene for chloroplast glyceraldehyde-3-phosphate dehydrogenase from maize 总被引:19,自引:0,他引:19
Henner Brinkmann Pascal Martinez Françoise Quigley William Martin Rüdiger Cerff 《Journal of molecular evolution》1987,26(4):320-328
Summary The nuclei of plant cells harbor genes for two types of glyceraldehyde-3-phosphate dehydrogenases (GAPDH) displaying a sequence divergence corresponding to the prokaryote/eukaryote separation. This strongly supports the endosymbiotic theory of chloroplast evolution and in particular the gene transfer hypothesis suggesting that the gene for the chloroplast enzyme, initially located in the genome of the endosymbiotic chloroplast progenitor, was transferred during the course of evolution into the nuclear genome of the endosymbiotic host. Codon usage in the gene for chloroplast GAPDH of maize is radically different from that employed by present-day chloroplasts and from that of the cytosolic (glycolytic) enzyme from the same cell. This reveals the presence of subcellular selective pressures which appear to be involved in the optimization of gene expression in the economically important graminaceous monocots. 相似文献
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Antigenic material obtained by phenol-water extraction from Providencia rettgeri strains, Escherichia coli O:14 strains, and mutants of the E. coli O:14 strain were examined by the passive (indirect) hemagglutination technique, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and by immune blotting (lipopolysaccharide (LPS) blotting). Providencia rettgeri 965, like E. coli O:14, was demonstrated to have an enterobacterial common antigen (ECA) in the immunogenic form but, unlike E. coli O:14, it possessed characteristics of a smooth strain. Two populations of molecules were observed to occur in P. rettgeri 965 phenol-water extracts: one consisting of LPS identifiable with specific O antisera and the other of ECA molecules identifiable with E. coli O:14 antiserum or with a monoclonal antibody against ECA. 相似文献
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Young hyphae ofNeurospora crassa were made permeable to UDP-glucose and trypan blue by treatment with toluene-ethanol and filipin. Less than 2% of treated cells survived treatment with 8% and 16% toluene-ethanol, while 25% survived treatment with 4% toluene-ethanol. Similarly, 98% of treated cells were killed by treatment with 16 g/ml filipin. Electron microscopy revealed that toluene-ethanol-treated cells lost pieces of plasma membrane and contained a number of vacuole-like structures; filipin-treated cells were less affected. Both filipin- and toluene-ethanol-treated cells were able to incorporate UDP-glucose into insoluble material (likely glycogen and glucan). 相似文献
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Cotranscription of the S10- and spc-like operons in spinach chloroplasts and identification of three of their gene products 总被引:8,自引:0,他引:8
The organisation and expression of the rpl22, rps3, rpl16 and rpl14 genes, which belong to the S10- and spc-like operons of spinach chloroplasts, have been studied. Northern experiments and nuclease S1 mapping show that the two operon-like groups of genes are cotranscribed. It is demonstrated that the intron-containing rpl16 gene is spliced in vivo. Based on amino acid composition and protein sequence data, the products of the rpl22, rpl16 and rpl14 genes are identified respectively as the spinach chloroplast ribosomal proteins CS-L13, CS-L24 and CS-L29. The rpl22 gene product is a 5S rRNA binding protein and therefore is distinguishable from the homologous Escherichia coli L22 ribosomal protein. 相似文献
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Synthesis and biological activity of an azido derivative of paclobutrazol, an inhibitor of gibberellin biosynthesis 总被引:1,自引:1,他引:0 下载免费PDF全文
Hallahan DL Heasman AP Grossel MC Quigley R Hedden P Bowyer JR 《Plant physiology》1988,88(4):1425-1429
A photolabile azido derivative of the kaurene oxidase inhibitor 1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-l-yl) pentan-3-ol (paclobutrazol) has been synthesized for use as a photoaffinity labeling agent. The compound was tested as an inhibitor of the oxidation of ent-kaurene catalyzed by cell-free preparations from endosperm of Cucurbita maxima. The I50 of the azido derivative was 9.5 nanomolar, which compares well with that of paclobutrazol (6.3 nanomolar in our measurements). The azido compound bound to Cytochrome P-450 in microsomes from Cucurbita maxima, and induced a Type II spectral change, with an apparent binding constant of 0.24±0.04 micromolar. 相似文献
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Tariq Ahmad Joanne C. Conover Martin M. Quigley Robert L. Collins Anthony J. Thomas Ralph B. L. Gwatkin 《Molecular reproduction and development》1989,22(4):369-373
Failure of epididymal spermatozoa from T/t mutant mice, but not from t/t individuals, to fertilize oocytes in vitro was partially overcome by opening a small aperture in the zona pellucida with acidified Tyrode's solution to permit direct access of the spermatozoon to the vitellus. This study provides a model system to evaluate requirements for successful zona drilling in the treatment of human infertility and further insights into the effects of the t complex on sperm fertility. 相似文献
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