In vitro studies on the induction of sporogenous tissue on leaves of cinnamon fern. II. Some aspects of carbohydrate metabolism

1973 ◽  
Vol 51 (2) ◽  
pp. 341-349
Author(s):  
William H. Harvey ◽  
James D. Caponetti
Keyword(s):  
Growth Rate ◽  
The Other ◽  
Gas Liquid Chromatography ◽  
Initial Part ◽  
Sporogenous Tissue ◽  
Storage Carbohydrate ◽  
Active Substrate ◽  
Carbohydrate Levels ◽  
Endogenous Carbohydrates

Since previous studies indicated a requirement for high levels of exogenous sucrose for induction of sporogenous tissue on excised set III leaves of cinnamon fern, the initial part of this study was performed to determine which hexose moiety of sucrose would serve as the more active substrate for sporangial induction. Glucose was found to be preferentially used for sporophyll induction and resulted in more extensive development than was seen in those leaves grown on fructose. Endogenous carbohydrate levels were measured by gas–liquid chromatography. In decreasing order of quantity, freshly excised primordia contained xylans, sucrose, fructose, β-D-glucose, xylose, and α-D-glucose. In leaves cultured on medium with sucrose levels of 2, 4, 6, 8, and 10%, the highest levels of all endogenous carbohydrates studied were found in leaves grown on medium with 2% sucrose. The xylans accumulated in leaves grown on medium with all sucrose levels and the amounts present were generally above those of uncultured primordia. The xylans represented the highest quantities of the carbohydrates measured and appeared to be a major storage carbohydrate in both cultured and uncultured leaves. The concentrations of sucrose, on the other hand, generally declined and were, in all cases, below the amounts in uncultured primordia. Increasing levels of exogenous sucrose above 2% generally resulted in a decline in levels of the other internal carbohydrates after [Formula: see text] weeks of culture, but the respective quantities were generally above those of freshly excised primordia. Enzymatic analysis failed to reveal any starch in the leaves. It is suggested that although increasing sucrose levels resulted in an increase in the growth rate, it would appear that sucrose is important in sporangial induction because of some mechanism in addition to its effect on an increasing growth rate.

Polyol and sugar content of terrestrial plants from continental Antarctica

1992 ◽  
Vol 4 (4) ◽  
pp. 413-420 ◽  
Author(s):  
David J. Roser ◽  
D.R. Melick ◽  
H.U. Ling ◽  
R.D. Seppelt
Keyword(s):  
Sugar Content ◽  
Dry Weight ◽  
Gas Liquid Chromatography ◽  
Terrestrial Plants ◽  
Total Carbohydrate ◽  
Antarctic Species ◽  
Prasiola Crispa ◽  
Windmill Islands ◽  
Carbohydrate Levels

Ethanol extractable polyols and sugars from the dominant cryptogams of the Windmill Islands, Wilkes Land, East Antarctica, were characterized and quantified by gas liquid chromatography. Arabitol, ribitol and mannitol were the major low molecular weight carbohydrates extracted from all eight species of lichen analysed. Total extractable carbohydrate levels (20–60 mg g−1 dry weight) were comparable to those for temperate lichens. Extracts of four common bryophyte species were dominated by sucrose, glucose and fructose; little polyhydric alcohol was detected except in the liverwort Cephaloziella exiliflora which contained a substantial proportion of mannitol. Total carbohydrate levels in the bryophytes (9–60 mg g−1 dry weight) were comparable to those in lichens. The compositions of eight species of algae varied considerably. Prasiola crispa, Desmococcus vulgaris and Schizogonium murale possessed sorbitol as their main constituent and had extractable carbohydrate contents comparable to those found in bryophytes on a dry weight or chlorophyll a content basis. The one snow alga with comparable carbohydrate levels, Mesotaenium berggrenii, contained sucrose, glucose, glycerol and a number of unidentified compounds. The remaining four species (Oscillatoria sp., Chloromonas sp.1 and Chlorosarcina sp. 2 and Chlamydomonas pseudopulsatilla) did not accumulate comparable levels of sugars and polyols. Though the levels of these compounds were much lower in the Windmill Islands lichens than in maritime Antarctic species, their content with respect to water content (0.7–7 molal) was well above that at which cold acclimated plants accumulate these compounds (c. 100–500 millimolal), and which provide cryoprotection in vitro. In the case of the bryophytes and algae, however, the in vivo content was generally < 100 millimolal.

Gene Disruption Studies of Penicillin-Binding Proteins 1a, 1b, and 2a in Streptococcus pneumoniae

1999 ◽  
Vol 181 (20) ◽  
pp. 6552-6555 ◽  
Author(s):  
JoAnn Hoskins ◽  
Patti Matsushima ◽  
Deborah L. Mullen ◽  
Joseph Tang ◽  
Genshi Zhao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Streptococcus Pneumoniae ◽  
Gene Disruption ◽  
Binding Proteins ◽  
The Other ◽  
Penicillin Binding Protein ◽  
Disruption Mutant ◽  
Penicillin Binding Proteins ◽  
Genes Encoding

ABSTRACT The effects of inactivation of the genes encoding penicillin-binding protein 1a (PBP1a), PBP1b, and PBP2a inStreptococcus pneumoniae were examined. Insertional mutants did not exhibit detectable changes in growth rate or morphology, although a pbp1a pbp1b double-disruption mutant grew more slowly than its parent did. Attempts to generate a pbp1a pbp2a double-disruption mutant failed. The pbp2amutants, but not the other mutants, were more sensitive to moenomycin, a transglycosylase inhibitor. These observations suggest that individually the pbp1a, pbp1b, andpbp2a genes are dispensable but that eitherpbp1a or pbp2a is required for growth in vitro. These results also suggest that PBP2a is a functional transglycosylase in S. pneumoniae.

scholarly journals Identity of the Growth-Limiting Nutrient Strongly Affects Storage Carbohydrate Accumulation in Anaerobic Chemostat Cultures of Saccharomyces cerevisiae

2009 ◽  
Vol 75 (21) ◽  
pp. 6876-6885 ◽  
Author(s):  
Lucie A. Hazelwood ◽  
Michael C. Walsh ◽  
Marijke A. H. Luttik ◽  
Pascale Daran-Lapujade ◽  
Jack T. Pronk ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
Glycogen Phosphorylase ◽  
Specific Growth ◽  
Glycogen Synthase ◽  
The Other ◽  
Carbohydrate Accumulation ◽  
Storage Carbohydrate ◽  
Chemostat Cultures ◽  
Limiting Nutrient

ABSTRACT Accumulation of glycogen and trehalose in nutrient-limited cultures of Saccharomyces cerevisiae is negatively correlated with the specific growth rate. Additionally, glucose-excess conditions (i.e., growth limitation by nutrients other than glucose) are often implicated in high-level accumulation of these storage carbohydrates. The present study investigates how the identity of the growth-limiting nutrient affects accumulation of storage carbohydrates in cultures grown at a fixed specific growth rate. In anaerobic chemostat cultures (dilution rate, 0.10 h−1) of S. cerevisiae, the identity of the growth-limiting nutrient (glucose, ammonia, sulfate, phosphate, or zinc) strongly affected storage carbohydrate accumulation. The glycogen contents of the biomass from glucose- and ammonia-limited cultures were 10- to 14-fold higher than those of the biomass from cultures grown under the other three glucose-excess regimens. Trehalose levels were specifically higher under nitrogen-limited conditions. These results demonstrate that storage carbohydrate accumulation in nutrient-limited cultures of S. cerevisiae is not a generic response to excess glucose but instead is strongly dependent on the identity of the growth-limiting nutrient. While transcriptome analysis of wild-type and msn2Δ msn4Δ strains confirmed that transcriptional upregulation of glycogen and trehalose biosynthesis genes is mediated by Msn2p/Msn4p, transcriptional regulation could not quantitatively account for the drastic changes in storage carbohydrate accumulation. The results of assays of glycogen synthase and glycogen phosphorylase activities supported involvement of posttranscriptional regulation. Consistent with the high glycogen levels in ammonia-limited cultures, the ratio of glycogen synthase to glycogen phosphorylase in these cultures was up to eightfold higher than the ratio in the other glucose-excess cultures.

scholarly journals Reconstitution of three-phase microtubule polymerisation dynamics

2016 ◽  
Author(s):  
Takashi Moriwaki ◽  
Gohta Goshima
Keyword(s):  
Growth Rate ◽  
Dynamic Instability ◽  
Molecular Level ◽  
The Other ◽  
Mitotic Kinase ◽  
The Core ◽  
Three Phase ◽  
Cytoplasmic Microtubules ◽  
Mitotic Cells

Cytoplasmic microtubules (MTs) undergo growth, shrinkage, and pausing. However, how MT polymerisation cycles are produced and spatiotemporally regulated at a molecular level is unclear, as the entire cycle has not been recapitulated in vitro with defined components. In this study, we reconstituted dynamic MT plus end behaviour involving all three phases, by mixing tubulin with five Drosophila proteins, EB1, XMAP215Msps, Sentin, kinesin-13Klp10A, and CLASPMast/Orbit. When singly mixed with tubulin, CLASPMast/Orbit strongly inhibited MT catastrophe and reduced the growth rate. However, in the presence of the other four factors, CLASPMast/Orbit acted as an inducer of pausing. The mitotic kinase Plk1Polo modulated the activity of CLASPMast/Orbit and kinesin-13Klp10A, and increased the dynamic instability of MTs, reminiscent of mitotic cells. These results suggest that five conserved proteins constitute the core factors for creating dynamic MTs in cells, and that Plk1-dependent phosphorylation is a crucial event for switching from the interphase to mitotic mode.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

ALDOSTERONE STIMULATION IN VITRO

1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Ammonium Chloride ◽  
Human Urine ◽  
Incubation Medium ◽  
The Other ◽  
Ammonium Ions ◽  
Response Curves ◽  
Urine Extract ◽  
Similar Dose ◽  
Aldosterone Production

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.

STEROID FORMATION IN PORCINE OVARIAN TISSUE IN VITRO

1970 ◽  
Vol 63 (3) ◽  
pp. 441-453 ◽  
Author(s):  
Asbjørn Aakvaag
Keyword(s):  
Liquid Scintillation ◽  
Specific Activity ◽  
Ovarian Tissue ◽  
Gas Liquid Chromatography ◽  
Similar Concentration ◽  
Endogenous Substrates ◽  
Exogenous Progesterone ◽  
Relative Utilization ◽  
Radioactive Substrate

ABSTRACT Slices of non-luteinized porcine ovaries have been incubated in the presence or absence of human chorionic gonadotrophin (HCG) and exogenous radioactive substrates. Progesterone, 17α-hydroxyprogesterone and androstenedione were isolated in a radiochemically pure form. The chemical mass and the specific activity were determined by gas liquid chromatography and liquid scintillation spectrometry. HCG stimulated the rate of formation of androstenedione in the absence of exogenous substrates with a factor of 4–8. In the presence of pregnenolone or progesterone at a concentration of about 2 × 10−6 mol/l the stimulatory effect of HCG was either abolished or markedly reduced. The conversion of exogenous progesterone to androstenedione was reduced in response to HCG indicating that the capacity of the tissue to convert progesterone to androstenedione was limited, and that the limit was reached at this rather low substrate concentration. These findings furthermore suggest that the endogenous rather than the exogenous radioactive substrate will be »preferred« by the tissue. The observations demonstrate the necessity of measuring both the radioactivity and the chemical mass of the products in investigations of this type using radioactive substrates. The formation of progesterone from endogenous substrates was also stimulated by HCG. [1-14C] acetate and [7α-3H]cholesterol were not utilized by the tissue for steroid formation. Exogenous [4-14C] pregnenolone and [7α-3H] progesterone in similar concentration were both utilized for production of 17α-hydroxyprogesterone and androstenedione. HCG had no effect on the relative utilization of the radioactive substrates.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel
Keyword(s):  
Biological Activity ◽  
Bacterial Growth ◽  
Xanthomonas Campestris ◽  
Plant Pathogens ◽  
Genetically Engineered ◽  
The Other ◽  
Computer Assisted ◽  
Signal Molecules ◽  
Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

Obtaining and Characterization of Alhagi persarum Boiss. et Buhse Callus Cell Cultures, Isoflavonoid Producers

2020 ◽  
Vol 36 (6) ◽  
pp. 35-48
Author(s):  
D.V. Коchkin ◽  
G.I. Sobolkovа ◽  
А.А. Fоmеnkov ◽  
R.А. Sidorov ◽  
А.М. Nоsоv
Keyword(s):  
Fatty Acids ◽  
Cell Culture ◽  
Liquid Chromatography ◽  
Secondary Metabolites ◽  
Cell Cultures ◽  
Mass Spectrometric ◽  
Mass Spectrometric Detection ◽  
Gas Liquid Chromatography ◽  
Callus Cell

The physiological characteristics of the callus cell cultures of Alhagi persarum Boiss et Buhse, a member of the legume family, widely used in folk medicine, have been studied. It was shown that the source of the explant was an important factor in the initiation of callusogenesis: more intense callusogenesis (almost 100%) was observed for explants from various organs of sterile seedlings, rather than intact plants (less than 30%). As a result, more than 20 lines of morphologically different callus cell cultures were obtained, and the growth parameters for the 5 most intensively growing lines were determined. The composition of fatty acids (FA) of total lipids and secondary metabolites in the most physiologically stable callus line Aр-207 was analyzed. Using capillary gas-liquid chromatography with mass spectrometric detection (GLC-MS), 19 individual C12--C24 FAs were identified, the main fraction of which were palmitic (~ 23%), stearic (~ 22%), linoleic (~ 14%) and α-linolenic (~ 33%) acids. The established atypical ratio of FAs (a simultaneous high content of both saturated FAs and polyunsaturated α-linolenic acid) is possibly due to the adaptation of cells to in vitro growth conditions. Phytochemical analysis of the secondary metabolites was carried out using ultra-performance liquid chromatography with electrospray ionization mass spectrometric detection (UPLC MS). Compounds belonging to different structural groups of isoflavones were found. Aglycones (calycosin, formononetin and afrormosin isomer), glucosides (formononetin glucoside), as well as esters of glucosides (malonylglycosides of calicosin, formononetin, afrormosin isomers, glycitein and genistein) were detected. These secondary metabolites are widespread in plants of the Fabaceae family; however, isoflavones are rare in representatives of the Alhagi genus. The presence of malonylated isoflavone glycosides in Alhagi spp. was shown for the first time. endemic plant species, Alhagi, in vitro cell culture, callus cell culture, isoflavones, fatty acids All studies were carried out using the equipment of the "Experimental Biotechnological Facility" and the "All-Russian Collection of Cell Cultures of Higher Plants" of IРР RAS. This work was supported by the Russian Foundation for Basic Research (RFBR), contract no.18-54-06021 (Az_a), and the Government of the Russian Federation, Megagrant Project no. 075-15-2019-1882.

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