Production of actinomycin D with immobilizedStreptomyces parvullus under nitrogen and carbon starvation conditions

1988 ◽  
Vol 10 (5) ◽  
pp. 331-336 ◽  
Author(s):  
Mina Dalili ◽  
Pao C. Chau
Keyword(s):  
Actinomycin D ◽  
Carbon Starvation ◽  
Starvation Conditions

Ethanol and carbon-source starvation enhance the accumulation of HSP80 in Neurospora crassa

1988 ◽  
Vol 34 (2) ◽  
pp. 162-168 ◽  
Author(s):  
H. S. Roychowdhury ◽  
M. Kapoor
Keyword(s):  
Heat Shock ◽  
Neurospora Crassa ◽  
Carbon Catabolite Repression ◽  
Normal Growth ◽  
Carbon Starvation ◽  
High Molecular Mass ◽  
Sucrose Starvation ◽  
Shock Response ◽  
Shock Proteins ◽  
Starvation Conditions

In Neurospora crassa, heat shock results in the induction of 9 to 11 heat shock proteins (HSP), of which HSP80 is the most abundant and the first to be synthesized. The induction of HSP80 was investigated during normal growth (2% sucrose) and under sucrose starvation. Transfer of mycelium to a medium supplemented with ethanol stimulated the synthesis of HSP80, even at the normal growth temperature of 28 °C. It was also synthesized under carbon starvation conditions, where the medium was supplemented with 0.02% sucrose, 0.3% acetate, 0.2% lactate, or ethanol. A 30–35 kilodalton polypeptide was induced by heat shock in carbon-sufficient media, but in 0.02% sucrose and 0.3% acetate containing media it was synthesized at normal temperatures. While the overall heat shock response remained unaltered in these cultures, the abundance of HSP90 and HSP70, relative to HSP80, was greater. HSP80 appears to be controlled by carbon-catabolite repression as well as heat shock. Another high molecular mass protein (tentatively designated alc'80') was observed to be induced by heat shock, provided carbon starvation conditions prevailed concurrently.

Behavior of Fusarium roseum 'Sambucinum' under carbon starvation conditions in relation to survival in soil

1969 ◽  
Vol 15 (1) ◽  
pp. 117-126 ◽  
Author(s):  
G. J. Griffin ◽  
T. Pass
Keyword(s):  
Latent Period ◽  
Direct Observation ◽  
Germ Tube ◽  
Carbon Starvation ◽  
Glucose Medium ◽  
Glucose Depletion ◽  
High Germination ◽  
Germ Tubes ◽  
Starvation Conditions ◽  
Exogenous Source

Direct observation of washed macroconidia of F. roseum 'Sambucinum' infested in rewetted soil and incubated at 6 °C indicated that germination increased to 79% at 4 days and increased slowly thereafter. Lysis of germ tubes was inhibited and most germ tubes were not lysed even after 48 days incubation. Small two- or three-celled macroconidia were commonly produced on germ tubes. In contrast, peak germination (39%) occurred at 2 days in rewetted soil incubated at 25 °C with germ tube lysis occurring rapidly between 4 and 8 days. Only sparse sporulation was observed. After 9 months, survival of F. roseum 'Sambucinum' was much greater in soil incubated at 6 °C than at 25 °C.Macroconidia required an exogenous source of carbon for high germination and formed one- or two-celled chlamydosporic macroconidia in media lacking exogenous carbon. After 9 months incubation under carbon starvation conditions at 25 °C chlamydosporic macroconidia had a longer latent period and a much slower rate of germination than macroconidia. Germinated macroconidia formed two- or three-celled macroconidia within 24 h when transferred to media lacking exogenous carbon. Four-celled macroconidia were produced by F. roseum 'Sambucinum' in a dilute glucose medium before exhaustion of the glucose while F. solani 'Coeruleum' formed chlamydospores in this medium after glucose depletion. Behavior of F. roseum 'Sambucinum' under carbon starvation conditions is similar to behavior in rewetted soil in the mode of sporulation and in the formation of chlamydosporic macroconidia, but differs by a lack of appreciable germination and by a greatly reduced lysis of fungal structures.

scholarly journals Autophagy induction under carbon starvation conditions is negatively regulated by carbon catabolite repression

2017 ◽  
Vol 292 (48) ◽  
pp. 19905-19918 ◽  
Author(s):  
Atsuhiro Adachi ◽  
Michiko Koizumi ◽  
Yoshinori Ohsumi
Keyword(s):  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Carbon Starvation ◽  
Autophagy Induction ◽  
Starvation Conditions

scholarly journals Uranyl Precipitation by Pseudomonas aeruginosa via Controlled Polyphosphate Metabolism

2004 ◽  
Vol 70 (12) ◽  
pp. 7404-7412 ◽  
Author(s):  
Neil Renninger ◽  
Roger Knopp ◽  
Heino Nitsche ◽  
Douglas S. Clark ◽  
Jay D. Keasling
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Carbon Starvation ◽  
Kinase Gene ◽  
Time Resolved ◽  
Uranyl Phosphate ◽  
Polyphosphate Degradation ◽  
Polyphosphate Metabolism ◽  
Native Host ◽  
Lethal Doses ◽  
Starvation Conditions

ABSTRACT The polyphosphate kinase gene from Pseudomonas aeruginosa was overexpressed in its native host, resulting in the accumulation of 100 times the polyphosphate seen with control strains. Degradation of this polyphosphate was induced by carbon starvation conditions, resulting in phosphate release into the medium. The mechanism of polyphosphate degradation is not clearly understood, but it appears to be associated with glycogen degradation. Upon suspension of the cells in 1 mM uranyl nitrate, nearly all polyphosphate that had accumulated was degraded within 48 h, resulting in the removal of nearly 80% of the uranyl ion and >95% of lesser-concentrated solutions. Electron microscopy, energy-dispersive X-ray spectroscopy, and time-resolved laser-induced fluorescence spectroscopy (TRLFS) suggest that this removal was due to the precipitation of uranyl phosphate at the cell membrane. TRLFS also indicated that uranyl was initially sorbed to the cell as uranyl hydroxide and was then precipitated as uranyl phosphate as phosphate was released from the cell. Lethal doses of radiation did not halt phosphate secretion from polyphosphate-filled cells under carbon starvation conditions.

Effect of Some Metabolic Inhibitors on Vinblastine-Induced Ribosomal-Granular Material Complexes

1971 ◽  
Vol 29 ◽  
pp. 548-549
Author(s):  
Awtar Krishan ◽  
Dora Hsu
Keyword(s):  
Granular Material ◽  
Rna Synthesis ◽  
Culture Medium ◽  
Actinomycin D ◽  
Metabolic Inhibitors ◽  
Protein And Rna Synthesis ◽  
Apparent Reduction ◽  
Plant Alkaloids ◽  
In Cells

Cells exposed to antitumor plant alkaloids, vinblastine and vincristine sulfate have large proteinacious crystals and complexes of ribosomes, helical polyribosomes and electron-dense granular material (ribosomal complexes) in their cytoplasm, Binding of H3-colchicine by the in vivo crystals shows that they contain microtubular proteins. Association of ribosomal complexes with the crystals suggests that these structures may be interrelated.In the present study cultured human leukemic lymphoblasts (CCRF-CEM), were incubated with protein and RNA-synthesis inhibitors, p. fluorophenylalanine, puromycin, cycloheximide or actinomycin-D before the addition of crystal-inducing doses of vinblastine to the culture medium. None of these compounds could completely prevent the formation of the ribosomal complexes or the crystals. However, in cells pre-incubated with puromycin, cycloheximide, or actinomycin-D, a reduction in the number and size of the ribosomal complexes was seen. Large helical polyribosomes were absent in the ribosomal complexes of cells treated with puromycin, while in cells exposed to cycloheximide, there was an apparent reduction in the number of ribosomes associated with the ribosomal complexes (Fig. 2).

Failure of Actinomycin-D to Inhibit Passive Avoidance Learning: A Confirmation

1966 ◽  
Author(s):  
Thomas K. Landauer ◽  
Lynn Eldridge
Keyword(s):  
Passive Avoidance ◽  
Avoidance Learning ◽  
Actinomycin D ◽  
Passive Avoidance Learning

ANALYSIS OF THE BIPHASIC ACTION OF GROWTH HORMONE IN VITRO ON THE RAT DIAPHRAGM

1968 ◽  
Vol 57 (3_Suppl) ◽  
pp. S19-S35 ◽  
Author(s):  
Å. Hjalmarson
Keyword(s):  
Growth Hormone ◽  
Actinomycin D ◽  
Accumulation Rate ◽  
Inhibitory Effect ◽  
Bovine Growth Hormone ◽  
Rat Diaphragm ◽  
Dual Nature ◽  
Hypophysectomized Rats ◽  
D 20

ABSTRACT In vitro addition of bovine growth hormone (GH) to intact hemidiaphragms from hypophysectomized rats has previously been found to produce both an early stimulatory effect lasting for 2—3 hours and a subsequent late inhibitory effect during which the muscle is insensitive to further addition of GH (Hjalmarson 1968). These effects on the accumulation rate of α-aminoisobutyric acid (AIB) and D-xylose have been further studied. In presence of actinomycin D (20 μg/ml) or puromycin (100 μg/ml) the duration of the stimulatory effect of GH (25 μg/ml) was prolonged to last for at least 4—5 hours and the late inhibitory effect was prevented. Similar results were obtained when glucose-free incubation medium was used. Preincubation of the diaphragm at different glucose concentrations (0—5 mg/ml) for 3 hours did not change the GH sensitivity. Addition of insulin at start of incubation could not prevent GH from inducing its late inhibitory effect, while dexamethasone seemed to potentiate this effect of GH. Furthermore, adrenaline was found to decrease the uptake of AIB-14C and D-xylose-14C in the diaphragm, but not to change the sensitivity of the muscle to GH. Preincubation of the diaphragm for 3 hours with puromycin in a concentration of 200 μg/ml markedly decreased the subsequent basal uptake of both AIB-14C and D-xylose-14C, in the presence of puromycin, and abolished the stimulatory effect of GH on the accumulation of AIB-14C. However, the effect of GH on the accumulation of D-xylose-14C was unchanged. The present observations are discussed and evaluated in relation to various mechanisms of GH action proposed to explain the dual nature of the hormone.

CONTRIBUTION TO THE EXISTENCE OF REGULATORY MECHANISMS AT THE ADRENAL LEVEL

1972 ◽  
Vol 70 (4) ◽  
pp. 741-757
Author(s):  
Otto Linèt
Keyword(s):  
Orotic Acid ◽  
Adrenal Glands ◽  
Actinomycin D ◽  
Delay Period ◽  
Regulatory Mechanisms ◽  
Leucine Incorporation ◽  
Total Period ◽  
Free Media

ABSTRACT Rat adrenal glands atrophied by the administration of cortisol acetate in vivo were used as a model for the study of early metabolic processes occurring in vitro. Atrophied adrenals incubated in the presence of 14C-leucine incorporated subnormal quantities of this amino acid per mg of protein for the first 120 min. When the incubation lasted for a total period of 180 or 240 min a supranormal rise in the 14C-leucine incorporation was observed. Similar changes occurred with some delay with regard to corticosterone production as expressed per 100 mg of tissue. No differences in 14C-leucine incorporation were observed between the control and atrophied adrenals in vivo. Homogenates from atrophied glands incorporated 14C-leucine to a greater extent than the control homogenates. The in vitro incorporation of 14C-orotic acid into the RNA was also higher in atrophied adrenals. The in vitro use of actinomycin D, cycloheximide and amphenone indicated that corticosterone production depended on the incorporation of 14C-leucine. The addition of cortisol to the incubation media markedly decreased the enhancement of 14C-lysine incorporation into the protein of atrophied adrenals. These, as well as additional results suggest rebound phenomena: once atrophic adrenals are transferred to cortisol-free media, reparative processes begin after a delay period. Such phenomena seem to be mediated by regulatory mechanisms at the adrenal level.

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.

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