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1.
Somatic hybridization of Lycopersicon peruvianum and Petunia hybrida was carried out to transfer cytoplasmic male sterility from Petunia to Lycopersicon. Cytological, morphological and biochemical analyses were performed to characterize the regenerated plants. Two regenerated plants, R3 and R6, were male sterile. R3 possessed chromosomes morphologically similar to those of both parental types. Leaf morphologies of these two plants and a third plant, R7, were intermediate between the two parents. The stability of RUBPCase was verified during parental plant development and after in vitro culture. Plant R7 presented a new form of the large subunit of RUBPCase.  相似文献   

2.
The terminal oxidases of Azotobacter vinelandii   总被引:2,自引:0,他引:2  
The terminal respiratory chain of the aerobic nitrogen-fixing bacterium Azotobacter vinelandii was investigated by photochemical action spectra. Terminal cytochrome oxidases a2, a1 and o were confirmed as being the terminal oxidases for the physiological substrates NADH and L-malate. TMPD/ascorbate, not giving coupled phosphorylation uses cytochrome a1 and possibly an o type. DCPIP/ascorbate, giving coupled phosphorylation uses neither cytochrome a1 nor a2.  相似文献   

3.
Bernier  R.  Rho  D.  Arcand  Y.  Desrochers  M. 《Biotechnology letters》1985,7(11):797-802
Summary The plasmid pRH271, harboring a xylanase gene cioned fromBacilius subtilis, has been transferred into a mutant ofE. coli SK2284 which allowed the release of part of the xylanase in the culture supernatant. Kinetic parameters of this recombinantE. coll strain were determined in microscale batch culture with and without the selective pressure of antibiotics. No significant difference in µmax was observed for the nontransformedE. coli strain when compared to the recombinant strain. However, K5 values for glucose were two times higher in the case of the recombinant strain. Preliminary study of xylanase production in a large batch farmenter was also described.  相似文献   

4.
The four stereoisomers of 25-hydroxyvitamin D3-26,23 lactone (25-OHD3-26,23 lactone) were tested against in vivo 25-OHD3-26,23 lactone to determine their relative competition in the radioligand binding assays for 25-OHD3 and 1,25-(OH)2D3. The 25R-OHD3-26,23S lactone and in vivo 25-OHD3-26,23 lactone behaved identically in the radioligand binding assay for 25-OHD3 and were ~5-fold more potent than 25-OHD3 at displacing 25-OH[3H]D3. The 25S-OHD3-26,23S lactone was the poorest competitor in this assay, requiring a 10-fold excess relative to 25-OHD3 to displace 50% of the 25-OH[3H]D3. The order of competition in the 25-OHD3 radioligand binding assay was 25R-OHD3-26,23S lactone = in vivo 25-OHD3-26,23 lactone ? 25S-OHD3-26,23R lactone > 25-OHD3 ? 25R-OHD3-26,23R lactone > 25S-OHD3-26,23S lactone. The order of competition in the 1,25-(OH)2D3 cytosol receptor assay was essentially reversed from the competition in the 25-OHD3 assay and was 25S-OHD3-26,23S lactone > 25-OHD3 ? 25S-OHD3-26,23R lactone > 25R-OHD3-26,23S lactone = in vivo 25-OHD3-26,23 lactone. When tested in a high-performance liquid chromatographic system which separates all four stereoisomers, the in vivo 25-OHD3-26,23 lactone comigrated with synthetic 25R-OHD3-26,23S lactone. These data firmly establish that the naturally-occurring 25-OHD3-26,23 lactone has the 25R, 23S stereochemistry. In addition, these data are the first to demonstrate that the four stereoisomers of 25-OHD3-26,23 lactone have different affinities for the plasma vitamin D binding protein and the 1,25-(OH)2D cytosol receptor.  相似文献   

5.
Summary Nine species of fungi viz.,Aspergillus niger,A. flavus,A. terreus,Fusarium solani,Mucor sp.,Neurospora crassa,Penicillium janthinellum,Trichoderma harzianum andTrichothecium roseum were evaluated for their potential to remove NH3–N from domestic waste water. Of the fungi tested,A. flavus was found to be the most effective in the removal of NH3–N. Maximum reduction (92%) of NH3–N by this organism was observed at pH 8.0 at 20°C.  相似文献   

6.
The status of glyoxalase-I was explored in exponentially growing and G1 arrested temperature sensitive (ts) cell division cycle (cdc) mutants of Saccharomyces cerevisiae. It was observed that the specific activity of this enzyme was correlated with overall growth status. The activity was high in actively growing cells and was low in G1 arrested cells. Specific activities of glyoxalase-I were also low in G1 arrested prolonged stationary phase (PSP) cells of S. cerevisiae and Candida albicans. The activity of glyoxalase-I recovered when G1 arrested S. cerevisiae (ts) cells were allowed to regrow under permissive conditions. Results demonstrate that although glyoxalase-I activity is a good indicator of cell growth status, it is not involved in cell cycle regulation of this eukaryotic organism.  相似文献   

7.
Summary Thermophilic degradation of sugar beet pulp was studied in batch cultures at 55°C by different associations of bacteria, includingClostridium thermocellum,Methanobacterium sp. andMethanosarcina MP.C. thermocellum produced acetate, succinate, methanol, ethanol, H2 and CO2. The coculture ofC. thermocellum andMethanobacterium sp. produced trace amounts of ethanol and succinate; acetate concentration was about three times higher than in theC. thermocellum monoculture. The association of this coculture withMethanosarcina MP produced 5.5 mmol CH4/g dry weight sugar beet pulp.  相似文献   

8.
Summary Two thermophilic strains of Lactobacillus were transformed by electroporation; L.fermentum with a maximum of frequency of 1×105/ug of plasmid vector pPSC20DNA and 1.4×103/ug pSA3DNA. L.helveticus showed a very low frequency of transformation, from 9 to 26 transformants/ug DNA in all the experiments carried out with both the vectors. While L.fermentum transformants were very stable, in L.helveticus the acquired plasmid was lost after 30–50 generations.  相似文献   

9.
Because of its highly unstable nature, TXA2, produced by platelet metabolism of arachidonic acid, does not lend itself to use as a receptor probe for its own receptor. As such, the stable TXA2/PGH2 antagonist, trans-13-azaprostanoic acid (trans-13-APA, 12b), was prepared as the [17,18 3H] derivative ([3H] trans-13-APA, 12c) to study this receptor and to better evaluate the mechanism of action of these azaprostanoids. Tritiated trans-13-APA, 12c, was prepared in nearly theoretical specific activity (57 Ci/mmole) from (17z)-trans-13-azaprost-17-enoic acid (11b) by catalytic tritiation. The unsaturated 11b was prepared by condensation of cis-7-amino-3-heptene (8) with 2-(6-carboxyhexyl) cyclopentanone (9), NaBH4 reduction, chromatography, and hydrolysis of the trans isomer so isolated. The olefins 11a and b were also of biochemical interest because of the unsaturation in the lower side chain. The presence of similar unsaturation in PGH3 (4) and TXA3 (3) renders these prostaglandins inactive as proaggregatory agents. Evaluation of the antiaggregatory activity of 11a and b indicated it to be about the same potency in inhibiting human platelet aggregation as the parent cis and trans-13-APAs, suggesting that introduction of a double bond at the 17 position in platelet prostaglandin antagonists is unlikely to result in enhanced antiplatelet activity.  相似文献   

10.
Hypocotyl derived protoplasts of B. juncea cv. RLM-198 were fused with mesophyll protoplasts of B. spinescens using polyethylene glycol to produce interspecific hybrids. Fusion products could be microscopically identified by characteristics of the protoplasts of both parents in the hybrid cells; they are colourless and vacuolated like the hypocotyl protoplasts and possess chloroplasts of the mesophyll protoplasts. The heterokaryotic fusion frequency was around 5%. However, the frequency of calli regenerating hybrid shoots was more than 10% of the regenerating calli. Putative somatic hybrids had morphological features characteristic of both the parents. Twelve plants analysed cytologically, possessed 52 chromosomes (26II) at meiosis representing the complete genomes of B. juncea (18II) and B. spinescens (8II). For esterase isozymes, the hybrids had bands of Doth the parents. Hybrid nature of some of the plants was confirmed by their close resemblance to B. juncea, chromosome number and isozyme bands of B. spinescens as in Rsp-19. Somatic hybrids had rudimentary, non-dehiscent anthers and completely sterile pollen. However, on back crossing with B. juncea, 10 out of 12 plants produced seeds and about 100 plants were realized.Abbreviations PEG Polyethylene glycol  相似文献   

11.
Summary Using pilot scale Wenger and Stake II reactors for prehydrolysing aspen and coniferous wood chips in the presence of SO2 catalyst, highly digestible lignocellulosic substrates were generated from which about 90% yields of hemicellulose mostly in monomeric form could be recovered. Simultaneous saccharification and fermentation (SSF) of these SO2 feedstocks by a mixed culture ofBrettanomyces clausenii andPichia stipitis R resulted in rapid and efficient fermentation giving a final yield of 369 and 360 L ethanol/tonne of the prehydrolysed woods, respectively. BecauseB. clausenii is an excellent cellobiose fermenter, no -glucosidase was needed during SSF.  相似文献   

12.
Phytochrome contents have been assayed in vivo in cell suspension cultures of Petroselinum hortense, Daucus carota and Glycine max. After transferring the cells to fresh medium phytochrome increased in parallel with the increase in cell number, whereas the amount of phytochrome per cell remained constant. The rate of phytochrome reaccumulation after pretreatment with 15 h red light was very similar in all three systems (2.8–3.6 (e) 10–5/h). Dark reversion and a fast and slow Pfr destruction were observed in all systems. The rate constants of these reactions varied strongly between the systems. The phytochrome systems of the cell cultures were compared with those of etiolated and light-grown seedlings and it was concluded that the cell suspension cultures of Petroselinum hortense and Daucus carota behaved similarly to light-grown seedlings. In contrast, those of Glycine max behaved similarly to a dark grown seedling.Abbreviations Pr'fr red, far-red absorbing forms of phytochrome - Ptot Pr+Pfr total amount of phytochrome - fwt fresh weight  相似文献   

13.
The synthesis of PGC2 methyl ester is described. Comparison of the synthetic material with the methyl ester prepared from natural PGC2 showed the two to be identical, thus confirming the structure assignment. The physical and biological data of PGC2 methyl ester are presented.Horton and Jones have recently shown that PGA1 (Ic) and PGA2 (Ia) are deactivated on incubation with cats blood (1,2). Jones has proposed that this deactivation involves the enzymic conversion of PGA (I) to an 11,12-double bond isomer (PGC, II) which is subsequently isomerized by base to the inactive PGB (III) (3). Structure assignment of the PGC's in the earlier study were based on chromatographic mobilities and uv and mass spectrometric properties. We report here a total synthesis of PGC2 methyl ester (IIb). Comparison of the biological and physical properties of this material with those of diazomethane-esterified natural material confirms the earlier structure assignment for PGC2 (IIa).  相似文献   

14.
Axillary buds from 5 genotypes of mulberry belonging to 4 species were cultured on modified MS basal medium. A total of 30 media combinations were tried for all the genotypes. The response of axillary buds and the requirement for growth regulators varied with genotype. In Morus indica BAP (0.25–0.5 mg/l), and in M. alba and M. rotondifolia GA3 (0.5–1.0 mg/l)were found to induce sprouting. Two genotypes of M. bombycis, namely Schimanochi and Mizusawa, developed healthy shoots on the incorporation of 2,4-D (0.5–1.0 mg/l) and BAP (0.5–2.0 mg/l), respectively. IBA (0.5 mg/l), along with cytokinin/auxin/gibberellin, had no effect on bud growth but helped root induction. Shoots developed from the axillary buds were further multiplied as nodal explants. MS basal medium supplemented with 0.5 mg/l IBA and LS vitamins was found best to produce healthy plantlets in all the genotypes. An average 89% survival was observed on transferring the plantlets to soil.Abbreviations MS Murashige and Skoog (1962) - LS Linsmaier and Skoog (1965) - IBA 3-indole-butyric acid - GA3 Gibberellic acid - BAP 6-Benzylaminopurine - Kn Kinetin - 2,4-D 2,4-Dichlorophenoxyacetic acid  相似文献   

15.
Plant regeneration from callus cultures of Durum and emmer wheat   总被引:1,自引:0,他引:1  
Callus cultures were initiated from isolated mature embryos of Triticum turgidum L. Thell ssps durum and dicoccum on a basal medium supplemented with 2,4-D, 2,4,5-Cl3POP or 2,4-D+CM. Shoot bud regeneration was observed on 2,4,5-Cl3POP medium. In both the cultivars of durum, further development of shoot buds occurred on transfer of tissues to basal medium whereas in dicoccum basal medium supplemented with coconut milk or coconut milk with NAA (0.2 mg/l) was necessary. The regenerated shoot buds were induced to root on basal medium supplemented with NAA. The in vitro obtained plants were transferred to soil and successfully grown to maturity. Chlorophyll variants were observed among the regenerated plants of dicoccum.Abbreviations BA benzyladenine - CM coconut milk - 2,4-D 2,4-dichlorophenoxyacetic acid - 2,iP 6---dimethylallylamine purine - IAA indoleacetic acid - NAA -naphthalene acetic acid - Kn kinetin - 2,4,5-Cl3POP 2,4,5-trichlorophenoxypropionic acid - MS modified Murashige and Skoog's medium - RH relative humidity - Z zeatin  相似文献   

16.
Protoplasts were isolated from leaves, shoots, cotyledons, ray florets and callus cultures of Dimorphotheca aurantiaca (syn. D. sinuata) (Cape Marigold, Star of the Veldt) and Rudbeckia hirta, R. laciniata and R. purpurea; species of ornamental value. For Dimorphotheca, plants were regenerated from protoplasts of all sources apart from the ray floret, whilst for the Rudbeckia species, although protoplast division was induced in most cases, only leaf mesophyll protoplasts of R. hirta c.v. Marmalade gave plants. The establishment of plant regeneration for these ornamental species, from protoplasts, now provides a basis for their somatic hybridisation.Abbreviations BAP 6-benzylaminopurine - IAA indole-3-acetic acid - NAA naphthaleneacetic acid - K kinetin - GA3 gibberellic acid - MS Murashige and Skoog (1962) - f.wt. fresh weight  相似文献   

17.
Summary Direct and maternal genetic effects were evaluated for maturing patterns of body weight in mice using a crossfostering design. Crossfostering was performed in one group using dams from populations selected for rapid growth rate (M16 and H6) and their reciprocal F1. crosses. A second crossfostering group consisted of dams from the respective control populations (ICR and C2) and their reciprocal F1. 's. Population differences were partitioned into direct and maternal effects due to genetic origin, correlated selection responses, heterosis and cytoplasmic or sex-linked effects. Degree of maturity was calculated at birth, 12, 21, 31 and 42 days of age by dividing body weight at each age by 63-day weight. Absolute and relative maturing rates were calculated in adjacent age intervals between birth and 63 days. Genetic origin effects (ICR vs. C2; M16 vs. H6) were significant for many maturity traits, with average direct being more important than average maternal genetic effects. In general, correlated responses to selection for maturity traits were larger in the M16 population (M16 vs. ICR) than in the H6 population (H6 vs. C2) and correlated responses in average direct effects were larger than average maternal effects. Positive correlated responses in average direct effects were found for relative maturing rates at all ages and for absolute maturing rates from 31 to 63 days. Apparent correlated responses in degree of maturity were negative for M16 and H6. However, further analysis suggested that the correlated response for degree of maturity in H6 may be positive at later ages and negative at earlier ages. Direct and maternal heterosis for degree of maturity was positive in the selected and control crosses. Absolute and relative maturing rates showed positive heterosis initially, followed by negative heterosis. Reciprocal differences due to the cytoplasm or sex-linkage were not important for patterns of maturity.Paper No. 5244 the Journal Series of the North Carolina Agricultural Experiment Station, Ealeigh, Animal Research Institute Contribution No. 683 and Agricultural University at Wageningen Contribution No. 654–490–12On leave from the Animal Research Institute, Agriculture Canada at Ottawa, OntarioOn leave from the Department of Animal Husbandry, Agricultural University at Wagenitgen, the Netherlands  相似文献   

18.
Suspension cultured cells of the liverwort, Reboulia hemisphaerica and of the moss, Barbula unguiculata were independently subcultured in the medium containing 2% glucose in the dark or in the light for more than one year, and the photosynthetic activities of the final cultures were determined. Throughout the culture period light-grown cells of both species contained high amount of chlorophyll (4 to 34 g mg–1 dry weight) and showed a high photosynthetic activity (10 to 84 mol O2 mg–1 chlorophyll h–1). Dark-grown cells of R. hemisphaerica showed the same level of chlorophyll content and photosynthetic O2 evolving activity as light-grown cells. Although chlorophyll content in dark-grown B. unguiculata cells was ten-fold lower than that in light-grown cells, the photosynthetic activity of these dark-grown cells was higher than that of light-grown cells based on chlorophyll content.  相似文献   

19.
The ability of various prostaglandins (PGs) to affect the in vitro anamnestic immune response of keyhole limpet hemocyanin (KLH)-primed rabbit popliteal lymph node cells was investigated. Of the four PGs studied (PGA1, PGE2 and PGF), PGE1 was found to have a stimulatory effect, whereas PGA1, PGE2 and PGF were ineffective in stimulating or inhibiting the in vitro anamnestic response. Under the conditions studied, a 3.5-fold increase in antibody production was obtained in PGE1-treated, KLH-stimulated cultures. Maximum enhancement was obtained when 0.2 μg of PGE1 were added at the time of culture initiation and were allowed to remain in contact with the lymph node cells for 24 hours.  相似文献   

20.
Summary The metabolite pattern of batch cultures ofLactobacillus casei LMG 6400,Clostridium butyricum LMG 1213t1 andEscherichia coli LMG 2093 was effected only for the latter organism when the H2 partial pressure was below 1 atmosphere: high hydrogen partial pressures increased the formate formation, low pressures gave rise to increased acetate production and higher cell yields.  相似文献   

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