Aspects of metabolic development in an illuminated synchronous culture of Scenedesmus obtusiusculus

1973 ◽  
Vol 51 (1) ◽  
pp. 113-120 ◽  
Author(s):  
Gaurangakumar Das
Keyword(s):  
Growth Phase ◽  
Ribonucleic Acid ◽  
Culture Medium ◽  
Deoxyribonucleic Acid ◽  
Dry Weight ◽  
Light Period ◽  
Weight Basis ◽  
Lipid Phosphorus ◽  
Acid Phosphate ◽  
Cellular Development

Developing synchronous cells of Scenedesmus obtusiusculus Chod. were investigated during the 15-h light period of the 24-h life cycle. Measurements were made of photosynthesis and of the chlorophyll, carotene, nucleic acid, and protein content, including intracellular phosphorus.Photosynthetic oxygen evolution (μmol/mg chlorophyll) increased during the early growing stage and declined gradually in the older cells. Chlorophyll, carotene, protein, ribonucleic acid, and ribonucleic acid phosphate of these cells increased during the growth phase (dry weight basis) and declined in the sporulating phase, whereas the deoxyribonucleic acid and deoxyribonucleic phosphate decreased during the growth phase. Deoxyribonucleic acid increased slightly in the sporulating phase, but deoxyribonucleic acid phosphate remained relatively constant during this period. When calculated on a per cell basis, ribonucleic acid and ribonucleic acid phosphate increased steadily throughout the period of observation, whereas deoxyribonucleic acid and deoxyribonucleic acid phosphate remained constant during the first 5 h and then increased gradually. Analysis of the intracellular distribution of phosphorus(dry weight basis) revealed that methanol-soluble (lipid) phosphorus decreased steadily with cell growth, whereas the content of acid-soluble phosphorus and ethanol–ether-soluble (lipid) phosphorus fluctuated markedly. The pH of the culture medium increased concomitantly with cellular development during the light period.

Composition of Methanospirillum hungatii GP1 during growth on different media

1980 ◽  
Vol 26 (5) ◽  
pp. 577-582 ◽  
Author(s):  
C. Breuil ◽  
G. B. Patel
Keyword(s):  
Protein Content ◽  
Ribonucleic Acid ◽  
Acid Content ◽  
Deoxyribonucleic Acid ◽  
Synthetic Medium ◽  
Density Measurement ◽  
Dry Weight ◽  
Weight Basis ◽  
Total Carbohydrate ◽  
Mineral Salts

Growth of Methanospirillum hungatii GP1 as determined by optical density measurement was comparable to growth assessed by cell dry weight, ribonucleic acid content, and deoxyribonucleic acid content. Cultivation of M. hungatii on synthetic medium containing mineral salts, vitamins, and acetic acid indicated that, on a dry weight basis, cell constituents such as protein (71%), ribonucleic acid (15.8%), deoxyribonucleic acid (1.6%), and total carbohydrate (3.2%) did not vary significantly with the growth phase. Cells grown in the synthetic medium supplemented with yeast extract and tryptone had slightly higher protein content (76%), but the concentrations of the other cell constituents were similar and did not fluctuate much during growth. Nitrogen limiting growth resulted in somewhat lower ribonucleic acid content as well as slightly higher protein content than that in cells grown in nonlimiting medium. Methanospirillum hungatii did not accumulate any of the commonly known reserve materials under nitrogen or carbon and hydrogen limiting growth.

scholarly journals THE DEVELOPMENT IN VITRO OF PARTICLES FROM CYTOPLASM

1958 ◽  
Vol 107 (5) ◽  
pp. 769-782 ◽  
Author(s):  
Eric L. Nelson
Keyword(s):  
Deoxyribonucleic Acid ◽  
Dry Weight ◽  
Weight Basis ◽  
Spherical Particles ◽  
Red Cell ◽  
Practical Applications ◽  
Unknown Factor ◽  
Development In Vitro ◽  
Ph Range

Spherical particles, 1 to 10 microns in diameter, resulted from the incubation at 37°C. of distilled water lysates of erythrocytes with deoxyribonucleic acid (DNA). The particles consisted of 88 per cent hemoglobin and 12 per cent DNA (dry weight basis). An unknown factor, presumably an enzyme, present only in fresh red cell lysates, was required for particle development. Particle size was a function of the pH of the reaction mixture. The pH range was 4.8–5.8. It was possible to trap extraneous proteins and polysaccharides in pockets within the hemoglobin particles during their development to the exclusion of some of the hemoglobin. The amount of any one substance so trapped was proportional to its concentration in the reaction mixture. Some practical applications of the particles, as a means for making particulate various soluble substances (enzymes, antigens, antibiotics), are suggested.

The physiology of growth in Subterranean clover. II. The dynamics of leaf growth

1970 ◽  
Vol 18 (2) ◽  
pp. 149 ◽  
Author(s):  
RF Williams ◽  
. Rijven.A.H.G.C
Keyword(s):  
Cell Wall ◽  
Ribonucleic Acid ◽  
Deoxyribonucleic Acid ◽  
Vascular System ◽  
Leaf Growth ◽  
Subterranean Clover ◽  
Dry Weight ◽  
Protein Nitrogen ◽  
Wall Materials ◽  
Cell Wall Materials

This study extends the account of the development of the fourth leaf of subterranean clover. In particular, the four leaf constituents deoxyribonucleic acid, ribonucleic acid, proteins, and cell wall materials are expressed on whole leaf and cell bases. Form change in the leaf is illustrated with perspective elevations for some early stages. Cell number increases exponentially until day 13, with a mean generation time of 18 hr. The final number per leaf is c. 6.5 million, and deoxyribonucleic acid phosphorus is estimated as 0.197 pg per cell. The leaf is highly succulent, with a maximum water content of 478 % dry weight. Soluble constituents are also high, with a maximum of 39 % of the dry matter. The absolute amounts of ribonucleic acid phosphorus and protein nitrogen are maximal on days 19 and 25 respectively, with losses of about 60% by day 36. Cell wall materials increase from 8 to 57 % of the residual dry weight during a period of 4 days prior to emergence. This is shown to be due to the concurrent differentiation of the vascular system and the growth of 3000 leaf hairs. Changes on a per cell basis are recorded, and the concept of relative growth rate is used to extend the analysis of the data. Rates of production of one constituent per unit of another are also presented and discussed.

EFFET DE L’ENDURCISSEMENT A LA GELEE SUR LA TENEUR EN MATIERE SECHE, EN PHOSPHORE LIPIDIQUE ET EN PROTEINES SOLUBLES ET INSOLUBLES DU BLE D’HIVER

1977 ◽  
Vol 57 (2) ◽  
pp. 555-561 ◽  
Author(s):  
C. WILLEMOT ◽  
H. J. HOPE ◽  
L. PELLETIER ◽  
J. LANGLOIS ◽  
R. MICHAUD
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Weight Basis ◽  
Lipid Phosphorus ◽  
Fresh Weight ◽  
General Increase ◽  
Frost Hardening ◽  
Protein Membrane ◽  
Cell Components ◽  
Membrane Components

During frost hardening of winter wheat (Triticum aestivum cvs. Kharkov 22 M.C., hardy, and Champlein, less hardy) fresh and dry weights, lipid phosphorus and soluble and insoluble proteins were determined. Percentage dry matter of the tissues doubled in both cultivars. When results are expressed per plant and per gram fresh weight, lipid phosphorus and soluble and insoluble proteins increased, while they decreased on a dry weight basis. There was therefore apparently no enrichment of the tissues in membranes in comparison with the other cell components but rather a general increase in dry weight. The observed changes occurred to the same extent in both cultivars and thus cannot explain varietal differences in frost hardiness. There was little correlation between the changes in lipids and protein. Lipid and protein membrane components appear therefore to have changed independently.

CHANGES IN THE DRY WEIGHT, PROTEIN, NUCLEIC ACID, AND CHLOROPHYLL CONTENTS OF GROWING PEA LEAVES

1961 ◽  
Vol 39 (4) ◽  
pp. 891-900 ◽  
Author(s):  
Robert M. Smillie ◽  
G. Krotkov
Keyword(s):  
Ribonucleic Acid ◽  
Soluble Protein ◽  
Deoxyribonucleic Acid ◽  
Higher Plants ◽  
Growth Period ◽  
Dry Weight ◽  
Cell Number ◽  
Chlorophyll Contents ◽  
Weight Protein ◽  
Protein Nucleic Acid

Pea leaves of different ages were harvested over a 10-day growth period and were analyzed for the following: fresh weight, dry weight, cell number, chlorophyll, soluble protein, ribonucleic acid, and deoxyribonucleic acid. The chlorophyll content increased rapidly during early leaf expansion, then remained fairly constant. Only small differences were found in the percentage of soluble protein in the leaves during their development. In contrast, the ribonucleic acid and deoxyribonucleic acid levels in the leaves decreased continuously as the leaves aged. These results are discussed in relation to similar analyses performed on leaves from other higher plants.

Influence of calcium on the metabolism of chlorophyll, carotene, nucleic acid, and protein in Scenedesmus

1973 ◽  
Vol 51 (1) ◽  
pp. 121-125 ◽  
Author(s):  
Gaurangakumar Das
Keyword(s):  
Nucleic Acid ◽  
Protein Content ◽  
Dna Content ◽  
Culture Medium ◽  
Growth Period ◽  
Dry Weight ◽  
Weight Basis ◽  
Carotene Content ◽  
Calcium Supply

The influence of calcium supply on the chlorophyll, carotene, nucleic acid, and protein content in Scenedesmus obtusiusculus Chod. was investigated. Evidence showed that upon addition of calcium-starved cells to a culture medium containing calcium, the levels of all these components increased slowly for 15 h. During the next 33 h chlorophyll and carotene content increased more rapidly, and the chlorophyll a:b ratio also increased. During this growth period, both RNA and protein content increased linearly whereas DNA content did not increase on a dry weight basis throughout the period of observation.

scholarly journals Phytochrome Regulation of Photosynthate Partitioning in Watermelon Plants Exposed to End-of-day Light Treatments

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 491A-491
Author(s):  
N.K. Damayanthi Ranwala ◽  
D.R. Decoteau ◽  
R.T. Fernandez
Keyword(s):  
Growth And Development ◽  
Dry Weight ◽  
Specific Weight ◽  
Light Period ◽  
Weight Basis ◽  
Photosynthate Partitioning ◽  
Low Intensity ◽  
Petiole Elongation ◽  
Development Processes ◽  
Growth Change

End-of-day (EOD) light treatments were used to study phytochrome involvement in photosynthesis and photosynthate partitioning in watermelon plants. Two-week-old plants were treated with brief low-intensity red (R) or far-red (FR) light for 9 days at the end of daily light period. Petiole elongation in the first two leaves was the first significant growth change in FR-treated plants compared to other plants after 3 days of treatments. This petiole elongation was accompanied by significantly higher photosynthate partitioning to petioles, even without increase in above-ground dry weight of plants. Net CO2 assimilation rate in the second leaf was significantly higher in FR treated plants on a weight basis after 3 days of treatments. Far-red-treated plants had lower chlorophyll content per leaf area and higher stem specific weight compared to R-treated plants after 3 and 6 days of treatments, respectively. Transpiration and stomatal conduction were higher in FR-treated plants compared to other treatments after 3 days of treatments. The EOD FR regulated growth and photosynthate partitioning patterns were reversible when FR treated plants were immediately followed by R. This implies EOD R: FR ratio acting through the phytochrome regulates the growth and development processes in watermelon plants.

Immunocytochemical studies on the behavior of RuBisCO and LHCP II during the cell cycle of synchronized Euglena gracilis

1990 ◽  
Vol 48 (3) ◽  
pp. 662-663
Author(s):  
Tetsuaki Osafune ◽  
Shuji Sumida ◽  
Tomoko Ehara ◽  
Eiji Hase ◽  
Jerome A. Schiff
Keyword(s):  
Cell Cycle ◽  
Immunoelectron Microscopy ◽  
Growth Phase ◽  
Euglena Gracilis ◽  
Dark Period ◽  
Light Period ◽  
Carboxylase Activity ◽  
Immunocytochemical Studies ◽  
Lhcp Ii

Changes in the morphology of pyrenoid and the distribution of RuBisCO in the chloroplast of Euglena gracilis were followed by immunoelectron microscopy during the cell cycle in a light (14 h)- dark (10 h) synchronized culture under photoautotrophic conditions. The imrnunoreactive proteins wereconcentrated in the pyrenoid, and less densely distributed in the stroma during the light period (growth phase, Fig. 1-2), but the pyrenoid disappeared during the dark period (division phase), and RuBisCO was dispersed throughout the stroma. Toward the end of the division phase, the pyrenoid began to form in the center of the stroma, and RuBisCO is again concentrated in that pyrenoid region. From a comparison of photosynthetic CO2-fixation with the total carboxylase activity of RuBisCO extracted from Euglena cells in the growth phase, it is suggested that the carboxylase in the pyrenoid functions in CO2-fixation in photosynthesis.

ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

1976 ◽  
pp. 213-225
Author(s):  
I.M. Ritchie ◽  
C.C. Boswell ◽  
A.M. Badland
Keyword(s):  
New Zealand ◽  
Dry Weight ◽  
Analytical Tool ◽  
Species Level ◽  
Weight Basis ◽  
Plant Identification ◽  
Leaf Fragment ◽  
Research Division ◽  
Or Groups ◽  
Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

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