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101.
Anna Nowakowska-Waszczuk Andrzej Sokoŀowski 《Applied microbiology and biotechnology》1987,26(4):363-364
Summary In an air-lift fermenter, the following production was obtained from 125 g sucrose in mineral medium at pH 2.5 : 15.76 g mycelium dry wt, 107.2 g citric acid anhydrous and 0.594 mol CO2 within 138 h (run I) and 13.72 g mycelium dry wt, 114.28 g citric acid and 0.516 mol CO2 within 144 h (run II). Initially, the carbon content of consumed sugar and products did not balance. At the end of fermentation, the carbon content of the products was 0.9%–5.5% higher than that of the consumed sugar. For the purpose of the calculations the carbon content in mycelium was accepted as 0.462.The work was a part of Project No 04.11 CPBP, topic No 2.24 相似文献
102.
Harry J. Klee Maria B. Hayford Stephen G. Rogers 《Molecular & general genetics : MGG》1987,210(2):282-287
Summary Cloning of genes by transformation with genomic banks and rescue of a phenotype has been extensively used in bacterial systems. This approach has not been possible in plant systems because of the large genome sizes and poor transformation frequencies of most plant species. Recent advances in plant transformation permit the generation of large numbers of transformants in petunia. We have used this system to rescue a model gene encoding resistance to kanamycin by shotgun cloning. The gene encoding neomycin phosphotransferase (NPTII) was introduced into the genome of Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation. A genomic bank of DNA from this tissue was constructed in a cosmid vector containing features which would allow its use in plant transformation. The unselected genomic bank was mobilized from Escherichia coli to A. tumefaciens and used to retransform petunia leaf discs. The rescued gene was identified by its ability to confer a kanamycin-resistant phenotype in petunia tissue. The presence of the NPTII gene was confirmed by nopaline assay and Southern blot analysis. This experiment demonstrates the feasibility of gene rescue, in certain circumstances, in plants. 相似文献
103.
The action of the herbicide glyphosate [N-(phosphonomethyl)-glycine] on phenolic metabolism and phenylalanine ammonia lyase (PAL; EC 4.3.1.5) activity was investigated in yellow nutsedge (Cyperus esculentus L.). Glyphosate caused significant increases in the amount of total soluble hydroxyphenolics in the three fractions studied (neutral, acid and residual). Qualitative and quantitative differences in relation to these fractions and the amount of applied glyphosate were observed. Most of the phenolic compounds which increased after glyphosate treatment were benzoic acids (gentisic. p -OH-benzoic, salicylic and vanillic). Gentisic acid showed the greatest increase in neutral and acid fractions, being twenty- and four-fold, respectively, of the amount found in the control. PAL activity was not affected by the lowest doses of glyphosate (10−4 and 10−3 M) , but a dramatic decrease in PAL activity was observed after 10−2 M treatment. These findings, together with the low levels of cinnamic acids measured in treated yellow nutsedge plants, suggest that PAL activity is only marginally involved in glyphosate action. Since the herbicidal action probably takes place at 5-enol-pyruvylshikimate-3-P synthase (EC 2.5.1.19), an alternative pathway to PAL in phenolic biosynthesis should be activated yielding benzoic acids. 相似文献
104.
Halińska, A. and Lewak, St. 1987. Free and conjugated gibberellins in dormancy and germination of apple seeds.
The presence of gibberellin A4 (GA4 ) was confirmed in partly stratified seeds of apple ( Malus domestica Borb., cv. Antonówka) by mass spectrometry of the methyl ester. Levels of free and conjugated gibberellins A4+7 and A9 changed during drying of mature seeds, during cold and warm stratification, as well as during germination of dormant and non-dormant embryos. The temporary rise in GA4+7 during cold stratification and during the culture of dormant embryos as well as the lack of it under conditions of warm stratification, allowed us to postulate a role for GA4+7 in the removal of dormancy. In addition, GA9 was absent in dormant embryos and increased during cold stratification and during the culture of non-dormant embryos. This suggests the involvement of GA9 , in induction of normal development of the seedling. The equivalence between changes in free and conjugated GAs suggests that formation and hydrolysis of conjugates are involved in the control of the physiologically active levels of free GA4+7 and GA9 . 相似文献
The presence of gibberellin A
105.
The effects of Rhizobium strain and its interaction with plant cultivar were examined in glasshouse-grownPhaseolus vulgaris in two experiments where the physiological attributes defining the symbiotic efficiency were determined.
Strains of Rhizobium significantly affected nodulation, rates of N accumulation, partitioning of N within the mature shoot
and remobilizaton of the N stored in the vegetative organs to the seeds.
The most efficient symbiosis (strain CO5 with Negro Argel), in comparison with the least efficient symbiosis (strain 127 K-17
with Venezuela-350) showed higher rates of C2H2 reduction from flowering to mid pod fill stage, evolved less hydrogen from nodules and showed higher rates of N transport
as well as higher percentages of ureide-N in the xylem sap. At maturity, the best cultivar/strain association exceeded the
total N accumulated in the seed and the harvest index of the poorest symbiosis in 88% and 20%, respectively. The other symbiotic
combinations were intermediate in all characteristics.
Nitrogen accumulation in plant shoot showed highly significant correlation with acetylene reduction rates, nodule relative
efficiency, total N transport in the xylem sap and percentage of N transported as ureides. 相似文献
106.
Carlos Eduardo Falavigna da Rocha Maria Helena Gonzaga de Carvalho Bjornber 《Hydrobiologia》1987,153(2):97-107
Cyclopid copepods collected mainly in aquatic microcosms and semiterrestrial habitats in the Juréia Ecological Reserve are studied. Hesperocyclops herbsti and Bryocyclops campaneri are described as new species and their taxonomical relationships discussed. Females of Muscocyclops operculatus (Chappuis) are redescribed and the males described for the first time. An emended diagnosis for Muscocyclops is proposed. 相似文献
107.
Pertussis Toxin Attenuates D2 Inhibition and Enhances D1 Stimulation of Adenylate Cyclase by Dopamine in Rat Striatum 总被引:2,自引:1,他引:1
The response of adenylate cyclase to GTP and to dopamine (DA) was investigated in synaptic plasma membranes isolated from rat striatum injected with pertussis toxin, which inactivates the inhibitory guanine nucleotide-binding regulatory protein (Ni) of adenylate cyclase. Pertussis toxin treatment reverted the inhibitory effects on the enzyme activity elicited by micromolar concentrations of GTP and reduced by 50% the DA inhibition of cyclase activity via D2 receptors. The toxin treatment enhanced the net stimulation of enzyme activity by DA in the presence of micromolar concentrations of GTP. However, the stimulatory effect of the selective D1 receptor agonist SKF 38393 was not significantly affected. The data indicate that Ni mediates D2 inhibition of striatal adenylate cyclase and participates in the modulation of D1 stimulation of the enzyme activity by DA. 相似文献
108.
109.
Anna Chrtková 《Plant Systematics and Evolution》1987,155(1-4):307-309
A new species,Lotus digii, has been found in Morocco growing on the coastal sandy soils. Further localities are from Algeria and Egypt. It should be expected also in Libya. 相似文献
110.