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121.
Analysis of Dioscorea deltoidea tissue cultures grown in the presence of 2,4-D, indole-3-butyric acid, isopentenyladenine, benzyladenine and GA singly and in combination showed that the medium with 2,4-D most consistently favored diosgenin production. GA and high benzyladenine concentrations were toxic. 相似文献
122.
Catabolism of flavonol glucosides was investigated in plant cell suspension cultures using kaempferol 3-O-β-d-glucoside and kaempferol 7-O-β-d-glucoside labelled with 14C either in the glucose or in the flavonol moiety. Catabolic rates of glucosides were compared with those of free glucose and kaempferol. All substrates were degraded efficiently by cell cultures of mungbean, soybean, garbanzo bean and parsley. Based on 14CO2-formation, glucose from position 3 of kaempferol is 3–5 times more rapidly metabolized than that from position 7. The flavonol nucleus from both isomers is, however, oxidized to the same extent with a considerable portion of the flavonol being incorporated into insoluble polymeric cell material. 相似文献
123.
The synthesis of cartilage collagen by rabbit and human chondrocytes in primary cell culture 总被引:2,自引:0,他引:2
Fred H. Schindler Marsha A. Ose Michael Solursh 《In vitro cellular & developmental biology. Plant》1976,12(1):44-47
Summary This report describes a method for preparing primary cell cultures of differentiated rabbit sternal and human vertebral cartilage
cells. These cell cultures were shown to synthesize primarily α1 chains, which is taken to mean that at least 82% of the collagen
produced is cartilage specific collagen (type II).
This work was supported in part by grant HD-05505 from NIH. 相似文献
124.
The hyphal walls of three mycobionts, isolated from the lichens Xanthoria parietina, Tornabenia intricata and Sarcogyne sp. were investigated by two techniques: microautoradiography of fungal colonies exposed to radioactive carbohydrate precursors; and binding, in vivo, of fluorescein conjugated lectins to hyphal walls of such colonies.N-[3H] acetylglucosamine was readily incorporated into tips, young hyphal walls and septa of the three mycobionts and the free-living fungus Trichoderma viride, but not into Phytophthora citrophthora, indicating that chitin is a major component of the mycobionts' hyphal walls. All three mycobionts, but neither of the free-living fungi, incorporated [3H] mannose and [3H] mannitol into their hyphal walls.Fluorescein-conjugated wheat germ agglutinin was bound to the hyphal walls of the three mycobionts and T. viride, but not to the walls of P. citrophthora; the binding pattern was similar to the grain pattern obtained in autoradiographs after short N-[3H] acetylglucosamine labelling. As wheat germ agglutinin binds specifically to chitin oligomers, the lectin binding tests further confirmed that chitin is a mycobiont hyphal wall component.Binding characteristics of several fluorescein-conjugated lectins to the three mycobionts indicated that this technique can yield useful information concerning the chemical composition of hyphal wall surfaces.List of abbreviations FITC
fluorescein isothiocyanate
- WGA
wheat germ agglutinin
- TCA
trichloroacetic acid
- PNA
peanut agglutinin
- LA
lotus agglutinin
- Glc NAc
N-acetylglucosamine
- ConA
concanavalin A
- SBA
soybean agglutinin
- WBA
waxbean agglutinin
Part of an M.Sc. thesis submitted by A. Braun to the Department of Botany, Tel Aviv University. 相似文献
125.
In axenic Chlorella pyrenoidosa Chick cultures, extracellular release was linear with time, but plateau-type curves were obtained in cultures with added bacteria. Initial rates of excretion were identical in both, systems. Kinetics of extracellular release in axenic Anabaena flos-aquae (Lyng.) Bréb. cultures were more complex than in Chlorella but the initial excretion rates were identical in axenic and mixed algal-bacterial cultures. In lakewater, extracellular release kinetics resemble the pattern in mixed Chlorella-bacteria cultures. An explanation is an initial lag in bacterial utilization of algal extracellular products. As a result, both in situ and in the laboratory, consecutive short, experiments give higher excretion rates than single long incubations. It is suggested that the former are close to total or gross extracellular release rates whereas the latter give net values, detecting only substances not, removed by heterotrophs. 相似文献
126.
Resuspension cultures of Gibberella fujikuroi, strain GF-1a, were shown to metabolise potassium [3′-13C] mevalonate to 13C-enriched C19-gibberellins, plus 13CO2 (derived from the loss of carbon-20). The formation of [13C]-gibberellins could be observed in vivo using 13C NMR; however that of 13CO2 could not. In contrast, removal of the mycelium and concentration of the filtrate at pH 12 enabled the 13CO2 produced to be observed using 13C NMR. During incubations of H14CO2Na with this fungus, complete conversion to other radioactive products was observed, and the significance of these results in the light of previous work is discussed. 相似文献
127.
G.Brian Lockwood 《Phytochemistry》1981,20(6):1463-1464
Orientalidine, isothebaine and sanguinarine were isolated from callus cultures of Papaver bracteatum when grown on M & S medium with various horm 相似文献
128.
Thomas G. Tornabene 《Journal of molecular evolution》1978,11(3):253-257
Summary
Halobacterium cutirubrum was successfully cultivated under aerobic and microaerobic conditions. The early stationary phase of growth was obtained at 2.2 days and 45–55 days for aerated and non-aerated cultures, respectively. The dry cell yields were 0.7–1.2 gm/l in all preparations grown to early stationary growth phase. The cellular ratio of squalene to dihydro- and tetra-hydrosqualene decreased proportionately with decreased aeration rates. 相似文献
129.
Anna Kletzmayr Flurina Clement Frey Miriam Zimmermann Daniel Eberli Christopher Millan 《Biotechnology journal》2020,15(5)
The microenvironment plays a major role in conferring chemoresistance to cancer cells. In order to better inform clinical response to chemoresistance, preclinical models that recapitulate its hallmark features are needed to enable screening for resistance‐specific therapeutic targets. A novel platform for seeding cancer cells in 3D hydrogels is presented utilizing derivatives of chitosan and alginate that, critically, is amenable to high throughput screening: cell seeding in hydrogels, media changes, dosing of anticancer compounds, and cell viability assays are all automated using a standard and commercially available liquid handling robot. Culture in these hydrogels elicits resistance in ovarian, lung, and prostate cancer cells to treatment by doxorubicin and paclitaxel. In correlation, proteomics analysis of SKOV3 cells cultured in 3D reveals enrichment of proteins associated with extreme drug resistance including HMOX1 and ALDH2. Subsequently, therapeutic antibodies targeted to tumor‐associated antigens upregulated in 3D cultures are shown to have higher efficacy compared to 2D cultures. Collectively, this automated 3D cell culture platform provides a powerful tool with utility in identification of drugs that may overcome chemoresistance. 相似文献
130.
Model‐assisted identification of metabolic engineering strategies for Jatropha curcas lipid pathways
Sandra M. Correa Saleh Alseekh Lucía Atehortúa Yariv Brotman Rigoberto Ríos‐Estepa Alisdair R. Fernie Zoran Nikoloski 《The Plant journal : for cell and molecular biology》2020,104(1):76-95
Efficient approaches to increase plant lipid production are necessary to meet current industrial demands for this important resource. While Jatropha curcas cell culture can be used for in vitro lipid production, scaling up the system for industrial applications requires an understanding of how growth conditions affect lipid metabolism and yield. Here we present a bottom‐up metabolic reconstruction of J. curcas supported with labeling experiments and biomass characterization under three growth conditions. We show that the metabolic model can accurately predict growth and distribution of fluxes in cell cultures and use these findings to pinpoint energy expenditures that affect lipid biosynthesis and metabolism. In addition, by using constraint‐based modeling approaches we identify network reactions whose joint manipulation optimizes lipid production. The proposed model and computational analyses provide a stepping stone for future rational optimization of other agronomically relevant traits in J. curcas. 相似文献