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41.
Herbicide-resistant Indica rice plants from IRRI breeding line IR72 after PEG-mediated transformation of protoplasts 总被引:9,自引:0,他引:9
Swapan K. Datta Karabi Datta Nouchine Soltanifar Gunter Donn Ingo Potrykus 《Plant molecular biology》1992,20(4):619-629
The commercially important Indica rice cultivar Oryza sativa cv. IR72 has been transformed using direct gene transfer to protoplasts. PEG-mediated transformation was done with two plasmid constructs containing either a CaMV 35S promoter/HPH chimaeric gene conferring resistance to hygromycin (Hg) or a CaMV 35S promoter/BAR chimaeric gene conferring resistance to a commercial herbicide (Basta) containing phosphinothricin (PPT). We have obtained so far 92 Hgr and 170 PPTr IR72 plants from protoplasts through selection. 31 Hgr and 70 PPTr plants are being grown in the greenhouse to maturity. Data from Southern analysis and enzyme assays proved that the transgene was stably integrated into the host genome and expressed. Transgenic plants showed complete resistance to high doses of the commercial formulations of PPT. 相似文献
42.
Frank-Michael Stolz Hans-Peter Pfau Gernot Reipen Susanne Schnittger Karl-Heinz Grzeschik Ingo Hansmann 《Genomics》1991,11(4):948-955
Employing the flow-sorted chromosome 20-specific DNA library LL20NS01, we isolated seven novel unique poly- and monomorphic DNA markers specific to human chromosome 20. Initially, 201 phage clones were analyzed regarding insert size and repetitivity. By testing 14 single- and low-copy number clones for their ability to detect RFLPs, three polymorphisms were revealed by two probes, pFMS22-1.4 [D20S22] and pFMS76 [D20S23]. Seven of twenty probes (35%) were assigned to chromosome 20 using a somatic cell hybrid DNA panel. Five of them were regionally mapped by in situ hybridization. Three DNA markers, pFMS51 [D20S29], pFMS76 [D20S23], and pFMS106 [D20S30], were assigned to 20p11.2-p12, and two markers, pFMS22-1.4 [D20S22] and pFMS135 [D20S31], to 20q12-q13.3. Our new chromosome 20-specific DNA markers should be useful for the molecular characterization of this rather underpopulated human chromosome. 相似文献
43.
Chlamydia trachomatis contains a protein similar to the Legionella pneumophila mip gene product 总被引:15,自引:0,他引:15
A. G. Lundemose S. Birkelund S. J. Fey P. Mose Larsen G. Christiansen 《Molecular microbiology》1991,5(1):109-115
A 27kDa Chlamydia trachomatis L2 protein was characterized by the use of monoclonal antibodies and by two-dimensional gel electrophoresis. The protein was shown to be located in the membrane of reticulate bodies as well as elementary bodies. Its synthesis could be detected from 10 hours post-infection. Cloning and sequence analysis of the distal part of the gene revealed an open reading frame of 175 amino acids. Comparison of the deduced amino acid sequence with the NBRF data base revealed significant homology between the 27 kDa chlamydial membrane protein and the product of the macrophage infectivity potentiator (mip) gene of Legionella pneumophila. 相似文献
44.
Bente Christiansen Jens Pete Lomholt Kjell Johansen 《Environmental Biology of Fishes》1982,7(3):291-296
Synopsis Oxygen uptake (Vo
2) was measured in carp of approximately 40 cm length swimming at controlled variable oxygen tensions (Po
2). At Po
2> 120 mm Hg Vo
2 increased with an increase in swimming speed from 5.6 to 11.3 cm · sec–1. Extrapolation of Vo
2 to zero activity at Po
2 = 140 mm Hg revealed a standard O2 uptake of 36.7 ml O2 · kg–1 · h–1 at 20° C. At the lowest swimming speed (5.6 cm · s–1) the oxygen uptake increased when the water Po
2 was reduced. A near doubling in Vo
2 was seen at Po
2 = 70 mm Hg compared to 140 mm Hg. At higher swimming speeds in hypoxic water Vo
2 decreased relative to the values at low swimming speeds. As a result the slope of the lines expressing log Vo
2 as a function of swimming speed decreased from positive to negative values with decreasing Po
2 of the water. pH of blood from the caudal vein drawn before and at termination of swimming at Po
2 = 70 mm Hg and 100 mm Hg did not show any decrease in relation to rest values at Po
2 = 140 mm Hg. Blood lactate concentration did not increase during swimming at these tensions. 相似文献
45.
The membrane-bound (Na+ + K+)-activated ATPase (ATP phosphohydrolase, EC 3.6.1.3) system was treated with the nonionic detergent octaethylene-glycoldodecyl ether, yielding a transparent supernatant after centrifugation. The supernatant was highly active with both ATPase and p-nitrophenylphosphatase, with initial specific activities of 2300 mumol Pi released . mg-1 protein. h-1 and 350 mumol p-nitrophenol released.mg-1 protein.h-1, respectively. The supernatant was purified to 95--100%, with respect to the 96 000 dalton and the 56 000 dalton peptides. The solubilized enzyme was gel filtered in Sepharose 4B-Cl and displayed 2 peaks, both with catalytic activity. The low molecular weight particles eluted at Kav = 0.54, corresponding to a molecular weight of approximately 500 000 daltons and the particles had a specific activity of 2100 mumol Pi.mg-1 protein.h-1. Both peaks contained phospholipid with 60 mol phospholipid bound per 300 000 g protein. The low molecular weight particles had a molecular weight of 276 000 as determined by sedimentation equilibrium analysis. 相似文献
46.
K K?lendorf J S Christiansen P A Svendsen J Bojsen 《Hormone and metabolic research. Supplement series》1979,(8):205-206
The daily insulin requirements as calculated with a closed-loop system (Biostator), were used for insulin infusion with a portable, miniaturized pump in 6 juvenile-onset, insulin-requiring diabetics. Three diabetics were given insulin in a manner like that of the Biostator, e.g., maximal insulin infusion about 1 hour after start of meals. The MBG was 8.7 +/- 3.9 (SD) mmol/l. Three other diabetics had insulin in a fixed profile with peaks beginning simultaneously with meals. MBG of these patients was 4.4 +/- 1.9 mmol/l. Knowing the daily insulin dosage as calculated from the Biostator, normal blood glucose levels can be achieved with a fixed profile of insulin given by a portable pump. 相似文献
47.
Ulf Ingo Flügge Hans Walter Heldt 《Biochemical and biophysical research communications》1978,84(1):37-44
Phosphate transport across the chloroplast envelope is rapidly inactivated by the amino-group reagent 2,4,6-trinitrobenzene sulfonate. Subsequent exposure to [3H]NaBH4 leads to an incorporation of the trinitrophenyl moiety into envelope membrane preparations. From the membrane proteins only a polypeptide with 29000 dalton molecular weight is labelled. The inactivation of phosphate transport and the incorporation of radioactivity are both specifically reduced by the presence of substrates.The results lead to the conclusion that a polypeptide with a molecular weight of 29000 dalton and containing a lysyl residue at the substrate binding site is involved in the phosphate translocator function. 相似文献
48.
49.
Recovery of nitrogen fertilizer by traditional and improved rice cultivars in the Bhutan Highlands 总被引:1,自引:0,他引:1
Bhim Bahadur Ghaley Henning Høgh-Jensen Jørgen Lindskrog Christiansen 《Plant and Soil》2010,332(1-2):233-246
The recovery of soil derived nitrogen (NDFS) and fertilizer N (NDFF) was investigated in highland rice (Oryza sativa L.) fields in Bhutan, characterized by high inputs of farmyard manure (FYM). The effect of 60 kg N ha?1 (60 N) applied in two splits to a traditional and an improved cultivar, popular among the farmers, was investigated using the 15N isotope dilution technique. No differences were found between cultivars with respect to the uptake of NDFS and NDFF, but the improved cultivar yielded 27% more (P?≤?0.05) grain compared with the traditional cultivar. This was largely due to its greater harvest index (HI). The mean percentage recovery of fertilizer N (REN) applied at 45 days after transplanting (DAT) was 34% compared to 22% at 7 DAT, resulting in 56% greater uptake of NDFF at 45 DAT. The overall REN for both the improved and the traditional cultivars were 25.7% and 30% respectively, with no difference between cultivars, but REN decreased with increasing FYM inputs. Fertilizer N recommendations that allow for previous FYM inputs combined with applications timed to coincide with maximum crop demand (45 DAT), and the use of improved cultivars, could enhance N fertilizer recoveries (REN) and increase rice yields in the Bhutan Highlands. 相似文献
50.