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1.
Jerry W. McClure 《Phytochemistry》1974,13(7):1065-1069
Five-day-old etiolated barley shoots respond to brief illumination with red light by increasing their level of PAL ca 50% within 5 hr. When assayed s 相似文献
2.
The shikimate/arogenate pathway: Link between carbohydrate metabolism and secondary metabolism 总被引:2,自引:0,他引:2
Roy A. Jensen 《Physiologia plantarum》1986,66(1):164-168
3.
We investigated the synthesis and translocation of amino compounds in Parasponia, a genus of the Ulmaceae that represents the only non-legumes known to form a root nodule symbiosis with rhizohia. In the xylem sap of P. andersonii we identified asparagine. aspartate. glutamine, glutamated significant quantities of a non-protein amino acid. 4-methylglutamte(2-amino-4-methylpentanedioic acid). This identification was confirmed by two methods, capillary gas chromatography (GC) electron ionization (El) mass spectrometry (MS) and reverse phase high pressure liquid chromatography (HPLC) analysis of derivatized compounds. In leaf, root and nodule samples from P. andersonii and P. parviflora we also identified the related compounds 4-methyleneglutamate and 4-methyleneglulamine. Using 15N2 labelling and GC-Ms analysis of root nodule extracts we followed N2 fixation and ammonia assimilation in P. andersonii root nodules and observed Label initially in glutamine and subsequently in glutamate, suggesting operation of the glutamine synthetase/glutamine:2-oxoglutarate aminotransferase (GS/GOGAT) pathway. Importantly, we observed the incorporation of significant quantities of 15N into 4-methylglutamate in nodules, demonstrating the de nova synthesis of this non protein amino acid and suggesting a role in the translation of N in symbioticParasponia. 相似文献
4.
5.
When grown with nitrate as terminal electron acceptor both the soluble (periplasm, cytoplasm) and the membrane fraction of Spirillum strain 5175 exhibited high nitrite reductase activity. The nitrite reductase obtained from the soluble fraction was purified 76-fold to electrophoretical homogeneity. The enzyme reduced nitrite to ammonia with a specific activity of 723 mol NO
inf2
sup-
× (mg protein × min)-1. The molecular mass was 58±1 kDa by SDS-PAGE compared to 59±2 kDa determined by size exclusion chromatography under nondenaturing conditions. The enzyme (as isolated) contained 5.97±0.15 heme c molecules/Mr 58 kDa. The absorption spectrum was typical for c-type cytochrome with maxima at 280, 408, 532 and 610 nm (oxidized) and at 420, 523 and 553 nm (dithionite-reduced). The enzyme (as isolated) exhibited a complex set of high-spin and lowspin ferric heme resonances with g-values at 9.82, 3,85, 3.31, 2.95, 2.30 and 1.49 in agreement with data reported for electron paramagnetic resonance spectra of nitrite reductases from Desulfovibrio desulfuricans, Wolinella succinogenes and Escherichia coli.Abbreviations DNRA
dissimilatory nitrate reduction to ammonia
- EPR
electron paramagnetic resonance
- PAGE
polyacrylamide gel electrophoresis
- NaPi
sodium phosphate
- SDS
sodium dodecylsulfate 相似文献
6.
Protein composition of the glyoxysomal membrane 总被引:2,自引:0,他引:2
7.
Mathias Sprinzl Karl-Heinz Scheit Hans Sternbach Friedrich von der Haar Friedrich Cramer 《Biochemical and biophysical research communications》1973,51(4):881-887
2′-Deoxyadenosine and 3′-deoxyadenosine (cordycepin) can be incorporated into the 3′-terminal position of tRNAPhe by tRNA nucleotidyl transferase. tRNAPhe-C-C-2′dA and tRNAPhe-C-C-3′dA, missing the cis-diol group at the 3′-terminal end are resistant to periodate oxidation and are not able to form borate complexes. In aminoacylation experiments only the tRNAPhe-C-C-3′dA proved to be chargeable. 相似文献
8.
Incorporation of [14C]-phenylalanine and [14C]-methionine into cinnamon cuttings suggests that synthesis of eugenol from phenylalanine involves exchange of the terminal carbon in the side chain with that from a donor molecule such as methionine whereas synthesis of cinnamic aldehyde incorporates phenylalanine in toto. 相似文献
9.
A number of inducible plant responses are believed to contribute to disease resistance. These responses include the hypersensitive reaction, phytoalexin synthesis, and the production of chitinase, glucanase, and hydroxyproline-rich glycoproteins. Because of the coordinate induction of these responses, it has been difficult to determine whether they are functional defense responses, and if they are, how they specifically contribute to disease resistance. Recent developments in molecular biology have provided experimental techniques that will reveal the specific contribution of each response to disease resistance. In this paper, we describe a strategy to determine if the hypersensitive reaction is a functional plant defense mechanism. 相似文献
10.
Laboratory experiments have shown appreciable losses of ammonia after injection of anhydrous ammonia into dry and wet soils.
In this study losses of ammonia injected into a moist (tension 10 kPa), dry (tension 160 kPa) and a wet (tension 1.6 kPa)
sandy loam were measured under field conditions using wind tunnels. Losses were insignificant from a moist soil. However losses
from a dry and a wet soil were 20% and 50% of injected ammonia, respectively. From the dry soil, losses of gaseous ammonia
took place within the first hours after injection, which indicates a rapid transport through cracks and voids. From the wet
soil, 20% of the injected ammonia was lost more gradually between 6 h and 6 d. This indicates that upward movement of water
due to evaporation may be the cause of these ammonia losses which proceeded for longer periods. 相似文献