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51.
Tobacco Nuclear Genes for Photosystem I Subunits, psaD, psaE and psaH Share an Octamer Motif Bound with Nuclear Proteins 总被引:1,自引:0,他引:1
In Nicotiana sylvestris, nuclear-encoded photosystem I (PSI)genes, psaD, psaE and psaH, share an octamer motif bound withthree phosphoproteins. This motif is not found in the chloroplastgenome. From the view point of endosymbiont hypothesis, theseresults suggest that a set of ancient PSI genes acquired a commoncis-element in the nucleus after they were transferred fromthe ancestral organelle. (Received March 20, 1995; Accepted August 9, 1995) 相似文献
52.
A link between increased transforming activity of lymphoma-derived MYC mutant alleles, their defective regulation by p107, and altered phosphorylation of the c-Myc transactivation domain. 总被引:5,自引:4,他引:1 下载免费PDF全文
A T Hoang B Lutterbach B C Lewis T Yano T Y Chou J F Barrett M Raffeld S R Hann C V Dang 《Molecular and cellular biology》1995,15(8):4031-4042
53.
Keiko Yamamura Tsunehisa Sakurai Kohji Yano Takashi Osada Toshitaka Nabeshima 《Microbiology and immunology》1995,39(11):895-896
To examine the efficacy of sisomicin (SISO) incorporated into fibrin glue (FG) for the prevention of graft infection in animal models, the susceptibility to infection of Dacron grafts (control) and SISO-FG Dacron grafts following the inoculation of Staphylococcus aureus or S. epidermidis was compared. The results showed that SISO-FG Dacron grafts displayed resistance to graft infection. 相似文献
54.
Le Van Phung Tran Thi Bich Chi Hisako Hotta Eiko Yabuuchi Ikuya Yano 《Microbiology and immunology》1995,39(2):105-116
Viet nam is known as an endemic area of melioidosis but its etiologic agent originated in Viet nam was not extensively studied. For the first time, we analyzed the cellular lipid and fatty acid compositions of 15 Vietnamese isolates of Burkholderia pseudomallei, 10 from humans and 5 from the environment. Cellular lipid compositions were analyzed by two-dimensional thin-layer chromatography on silica gel G plates. Cellular fatty acid methyl esters were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The major lipids in all the isolates were phosphatidylglycerol (PG), two forms of phosphatidylethanolamine (PE-1 and PE-2), and two forms of ornithine-containing lipid (OL-1 and OL-2). PE-1 contained non-hydroxy fatty acids at both sn-1 and ?2 positions, while PE-2 possessed 2-hydroxy fatty acids and non-hydroxy fatty acids in a ratio of 1: 1. Since snake venom phospholipase A2 digestion of PE-2 liberated 2-hydroxy fatty acids, it was confirmed that these acids are at the sn-2 position of glycerol moiety. In both OL-1 and OL-2, amide-linked fatty acid was 3-hydroxy palmitic acid (3-OH-C16: 0), while ester-linked fatty acids were non-hydroxy acids in OL-1 and 2-hydroxy acids in OL-2. The total cellular fatty acid compositions of the test strains were characterized by the presence of 2-hydroxy palmitic (2-OH-C16: 0), 2-hydroxy hexadecenoic (2-OH-C16: 1), 2-hydroxy octadecenoic (2-OH-C18: 1), 2-hydroxy methylene octadecanoic (2-OH-C19CPA), 3-hydroxy myristic (3-OH-C14: 0) and 3-hydroxy palmitic (3-OH-C16: 0) acids. There were significant differences in the concentration of hexadecenoic (C16: 1), methylene hexadecanoic (C17CPA), octadecenoic (C18: 1) and methylene octadecanoic (C19CPA) acids among the Vietnamese isolates of B. pseudomallei. However, no significant difference was observed in cellular lipid and fatty acid components between strains of human and environmental origins. 相似文献
55.
Rice-barley synteny and its application to saturation mapping of the barley Rpg1 region. 总被引:4,自引:0,他引:4 下载免费PDF全文
A Kilian D A Kudrna A Kleinhofs M Yano N Kurata B Steffenson T Sasaki 《Nucleic acids research》1995,23(14):2729-2733
In order to facilitate the map-based cloning of the barley stem rust resistance gene Rpg1, we have demonstrated a high degree of synteny at a micro level between the telomeric region of barley chromosome 1P and rice chromosome 6. We have also developed and applied a simple and efficient method for selecting useful probes from large insert genomic YAC and cosmid clones. The gene order within the most terminal 6.5 cM of barley chromosome 1P was compared with the most terminal 2.7 cM of rice chromosome 6. Nine rice probes, previously mapped in rice or isolated from YAC or cosmid clones from this region, were mapped in barley. All, except one, were in synteny with the rice gene order. The exception, probe Y617R, was duplicated in barley. One copy was located on a different chromosome and the other in a non-syntenic position on barley chromosome 1P. The barley probes from this region could not be mapped to rice, but two of them were inferred to be in a syntenic location based on their position on a rice YAC. This work demonstrates the utility of applying the results of genetic and physical mapping of the small genome cereal rice to map-based cloning of interesting genes from large genome relatives. 相似文献
56.
Le Van Phung Yuki Han Shiro Oka Hisako Hotta Michael D. Smith Prapit Theeparakun Eiko Yabuuchi Ikuya Yano 《FEMS immunology and medical microbiology》1995,12(3-4):259-264
Abstract The serodiagnosis of melioidosis is commonly performed with tests using protein or polysaccharide as antigen. However, due to the low sensitivity, specificity and difficulty in the preparation of the antigens, more simple, precise and reproducible diagnostic tests were required. A purified glycolipid antigen (GL) which is a specific lipid component of Burkholderia pseudomallei has been used in an ELISA. With this antigen, specific immunoglobulin G (IgG) was detected in 49 out of 50 melioidosis sera. IgG was also detected in 2 out of 185 (Japanese) and 16 out of 181 (Vietnamese) control sera. Thus, the sensitivity was 98.0%, and specificity was 98.9% and 91.1% in the Japanese and Vietnamese sera, respectively. When the ELISA and indirect haemagglutination (IHA) tests were combined, a sensitivity of 100% and specificity of 97.8% were achieved. The advantages of the glycolipid antigen are ease of preparation, stability, high sensitivity and specificity. 相似文献
57.
Junichi Kitajima Tetsuya Komori Toshio Kawasaki Hans-rolf Schulten 《Phytochemistry》1982,21(1):187-192
From the aerial parts of Fritillaria thunbergii, three glycosidal Solanum alkaloids (basic steroid saponins) were isolated together with minor 相似文献
58.
We have found that biotin is synthesized in many species of cultured plant cells, e.g. Lavandula vera Labiatae), Nicotiana tabacum (Solanaceae) and Glycine max Leguminosae). Cultured green L. vera cells grown under light contained the greatest amounts of free biotin of the cells studied although the specific amounts varied among the cell lines. Cell lines were selected after their free biotin contents had been analysed. Cells containing large amounts of free biotin were cultured repeatedly, analysed and reselected. Lines with high levels of free biotin were obtained from cells which survived on a medium containing pimelic acid and l-alanine or from gamma irradiated cells. One L. vera cell line obtained from irradiated cells contained seven times the amount of free biotin found in the original unselected cultured cells and four and a half times that found in the leaves. 相似文献
59.
The biological characteristics of a heterophile protein (HP) in peritoneal exudate from mice, hamsters, rats, and guinea pigs infected with Toxoplasma gondii were studied by immunofluorescence, immunoelectrophoresis and immunodiffusion techniques using specific antisera raised in rabbits. HP of mice had the highest antigenicity, HP of hamsters and rats had intermediate antigenicity and HP of guinea pigs had the lowest antigenicity. HP was found in normal peritoneal exudates from mice, hamsters and rats inoculated with paraffin oil instead of T. gondii and in normal guinea pig serum. HP was detected by the fluorescent antibody technique on the surface of T. gondii in peritoneal exudates of mice, but not on mouse peritoneal cells, and by the indirect fluorescent antibody technique on L cells infected with T. gondii and on free Toxoplasma derived from them, but not on uninfected L cells. T. gondii could make host cells produce HP to cover its surface for protection. The relation between HP from host cells and T. gondii is discussed. 相似文献
60.
T Kitagawa T Kanamaru H Wakamatsu H Kato S Yano Y Asanuma 《Journal of biochemistry》1978,84(2):491-494
A new method for the preparation of ampicillin-BSA conjugate by a three step procedure was developed. The first step is the introduction of a maleimide residue to ampicillin by a cross-linking reagent, MBS. The second step is reductive cleavage of disulfide bonds in BSA. The third step is thioether formation between the introduced maleimide residues and the reduced thiol groups. The obtained ampicillin-BSA conjugated raised an anti-ampicillin serum in rabbits. A new reagent, MPGS, was used for enzyme labelling of ampicillin to avoid immunological cross reaction. Using the enzyme labelled ampicillin and anti-ampicillin serum, enzyme immunoassay of ampicillin was successful in detecting 4 ng to 1 mug. Cross reactivities of anti-ampicillin to ampicillin analogs were studied by the enzyme immunoassay to find that the antiserum is specific to penicillin especially to ampicillin but hardly reacts with cephalosporins or the penicilloic acid derivative of ampicillin. 相似文献