PHOTOSYNTHESIS AND METABOLISM OF MARINE ALGAE: V. RESPIRATION AND METABOLISM OF C14-LABELLED GLUCOSE AND ORGANIC ACIDS SUPPLIED TO FUCUS VESICULOSUS

1963 ◽  
Vol 41 (1) ◽  
pp. 155-163 ◽  
Author(s):  
R. G. S. Bldwell ◽  
N. R. Ghosh
Keyword(s):  
Organic Acids ◽  
Marine Algae ◽  
Alginic Acid ◽  
Fucus Vesiculosus ◽  
Alcohol Extract ◽  
Sodium Salts ◽  
Uptake And Metabolism

Fronds of F. vesiculosus were supplied with glucose-UL-C14, pyruvate-2-C14, acetate-1-C14, acetate-2-C14, or formate-C14, the acids being presented as the sodium salts. The radioactivity of various fractions of the fronds as well as respired CO2 was determined after various times, and the distribution of radioactivity among the compounds present in the alcohol extract was determined. The contribution of glucose to respired CO2 was much less than that of the organic acids. However, although its uptake and metabolism were less, a large proportion of the glucose that was metabolized was converted to CO2. Glucose contributed somewhat to polysaccharides, but the organic acids were much better precursors of alginic acid. The pattern of labelling among soluble compounds, of which glycerol was especially prominent, indicated that several pathways of metabolism operated, involving both carboxylation and decarboxylation reactions.

Photosynthesis and metabolism of marine algae. VIII. Incorporation of 14C into the polysaccharides metabolized by Fucus vesiculosus during pulse labeling experiments

1972 ◽  
Vol 50 (1) ◽  
pp. 191-197 ◽  
Author(s):  
R. G. S. Bidwell ◽  
Elizabeth Percival ◽  
Berit Smestad
Keyword(s):  
Molecular Weight ◽  
Sequential Extraction ◽  
Marine Algae ◽  
Alginic Acid ◽  
Fucus Vesiculosus ◽  
Fresh Medium ◽  
Low Molecular Weight ◽  
Acid Extract ◽  
Highly Active ◽  
Residual Material

Samples of Fucus vesiculosus fronds were allowed to assimilate 14CO2 for 10 min and 3 h. In a second experiment fronds were allowed to grow for 10 min in 14CO2 and were then transferred to fresh medium containing 12CO2. Samples were taken immediately, after 30 min, and after 2 h. Sequential extraction and fractionation of the polysaccharides from each of the five samples gave 14C-labeled laminaran, xylogalactofucoglucuronan (A), xyloglucuronogalactofucan (B) (these polysaccharides are named in the order of the increasing proportions of their constituent sugars), fucoidan (C), alginic acid, and residual polysaccharide material containing mainly glucose with some galactose. The activities of each of the polysaccharides, the residual material, and their constituent sugars were measured. Highly active low molecular weight carbohydrates, present in the acid extract, are the suggested precursors of the polysaccharides. The fucose-containing polysaccharides represent the extremes of a family of polymers; it is postulated from these studies that (A) is transformed into fucoidan via polysaccharide (B) in this alga.

DARK FIXATION OF C14-BICARBONATE BY MARINE ALGAE

1963 ◽  
Vol 41 (3) ◽  
pp. 317-325 ◽  
Author(s):  
J. S. Craigie
Keyword(s):  
Organic Acids ◽  
Marine Algae ◽  
Total Radioactivity ◽  
Fucus Vesiculosus ◽  
Artificial Seawater ◽  
Dark Fixation

The ability of several multicellular marine algae to remove NaHC14O3 from seawater in darkness has been compared. Members of the Phaeophyta removed approximately four to eight times more isotope than did members of the Rhodophyta and Chlorophyta examined. After 2 minutes of dark fixation, aspartic and glutamic acids were the main compounds identified in both Fucus vesiculosus and Polysiphonia lanosa. Radioactivity appeared largely in citric plus isocitric acids in Fucus, whereas radioactive organic acids were not detected in Polysiphonia even after 30 minutes. Fractionation of F. vesiculosus after 2 hours of dark fixation showed that 95% of the total radioactivity recovered occurred in the fraction soluble in 70% acetone.Twenty-four hours of darkness immediately prior to a 2-hour dark fixation period reduced the total radioactivity incorporated to almost one-half of the control values. Either artificial seawater (one-fifth natural salinity) or a medium in which NaCl was substituted by KCl had little effect on the total radioactivity fixed during darkness. The distribution of isotope, however, showed some alterations.

EXCRETION OF COLORED ULTRAVIOLET-ABSORBING SUBSTANCES BY MARINE ALGAE

1964 ◽  
Vol 42 (1) ◽  
pp. 23-33 ◽  
Author(s):  
J. S. Craigie ◽  
J. McLachlan
Keyword(s):  
Ultraviolet Light ◽  
Alkaline Hydrolysis ◽  
Marine Algae ◽  
Elevated Temperatures ◽  
Surrounding Medium ◽  
Fucus Vesiculosus ◽  
Small Decrease

Normal, healthy thalli of Fucus vesiculosus have been shown to release into the surrounding medium yellow compounds which absorb ultraviolet light. A study of this phenomenon revealed that brief exposure to elevated temperatures (20 °C) increased the amount of pigment released. There was no difference in the production in light or darkness and only a small decrease with reduced salinity. The amount of pigmentation observed in the medium was directly proportional to the degree of alkalinity from pH 7 to pH 9.A number of other macrophytes and microphytes were examined and only those possessing physodes released substances giving a spectrum similar to that of F. vesiculosus.Isolation of the material, alkaline hydrolysis, and chromatography revealed phloroglucinol and several unidentified fluorescent substances. It appears that these materials were flavonols or catechin-type tannins.

PHOTOSYNTHESIS AND METABOLISM IN MARINE ALGAE: VII. PRODUCTS OF PHOTOSYNTHESIS IN FRONDS OF FUCUS VESICULOSUS AND THEIR USE IN RESPIRATION

1967 ◽  
Vol 45 (9) ◽  
pp. 1557-1565 ◽  
Author(s):  
R. G. S. Bidwell
Keyword(s):  
Sodium Carbonate ◽  
Marine Algae ◽  
Fucus Vesiculosus ◽  
Complex Compounds ◽  
Major Product ◽  
Dilute Acid ◽  
Active Metabolites

Samples of Fucus vesiculcsus fronds were permitted to assimilate 14CO2 for 5 h and were then maintained in alternating periods of light and darkness for 3 days. Samples were collected at intervals, and the radioactivity of various simple and complex compounds was measured. The major product of photosynthesis was mannitol; relatively small amounts of 14C entered other compounds. From its behavior, it appears that mannitol is the major substrate of respiration in these plants; there may be secondary substrates among the complex polysaccharides. The complex polysaccharides are not formed directly from mannitol in light, but from some common precursors, or else from a small isolated pool of mannitol which is separated from the main cellular supplies. In darkness, the complex polysaccharides appear to be derived from stored mannitol. One of the more active metabolites, judged from its behavior, is a component of the residue left after dilute acid and sodium carbonate extraction. This component undergoes turnover, i.e. breakdown and resynthesis from newly-acquired photosynthate in the light, and is formed from stored photosynthate in the darkness.

Proflavine binding and release by sensitive and resistant Bacillus subtilis

1970 ◽  
Vol 16 (10) ◽  
pp. 973-981
Author(s):  
Gy. Barabas ◽  
B. M. Mehta ◽  
D. J. Kushner
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Organic Acids ◽  
Resistant Strain ◽  
Binding Capacity ◽  
Sensitive Strain ◽  
Growth Media ◽  
Sodium Salts ◽  
Salts Of Organic Acids ◽  
Resistant Cells

Proflavine binding of a sensitive strain of Bacillus subtilis and of a resistant strain derived from it was compared. Proflavine was bound very rapidly and more was bound at 0 °C than at 37 °C. Boiling increased the proflavine-binding capacity at 37 °C of sensitive but not of resistant cells. The binding capacity of sensitive and resistant cells suspended in buffer was the same; this was also true in various growth media. If cells were able to grow in the presence of proflavine their proflavine content decreased.Bound proflavine was released when cells were treated with growth media or with the salts of growth media. Sodium salts of organic acids also caused a release. This effect seemed due to their Na+ content, and was somewhat higher for resistant than for sensitive cells. The mechanism of proflavine resistance in B. subtilis is probably different from that of Escherichia coli, which is thought to depend on an energy-driven release of bound proflavine.

scholarly journals SelectedAspects of Iodate and Iodosalicylate Metabolism in Lettuce Including the Activity of Vanadium Dependent Haloperoxidases as Affected by Exogenous Vanadium

Agronomy ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 1 ◽  
Author(s):  
Sylwester Smoleń ◽  
Iwona Kowalska ◽  
Mariya Halka ◽  
Iwona Ledwożyw-Smoleń ◽  
Marlena Grzanka ◽  
...  
Keyword(s):  
Nutrient Solution ◽  
Marine Algae ◽  
Higher Plants ◽  
Crop Plants ◽  
Lactuca Sativa L ◽  
Iodine Compounds ◽  
Iodine Treatment ◽  
Quantitative Changes ◽  
Hormone Analogs ◽  
Uptake And Metabolism

In marine algae, vanadium (V) regulates the cellular uptake of iodine (I) and its volatilization as I2, the processes catalyzed by vanadium-dependent haloperoxidases (vHPO). Relationships between I and vanadium V in higher plants, including crop plants, have not yet been described. Little is known about the possibility of the synthesis of plant-derived thyroid hormone analogs (PDTHA) in crop plants. The activity of vHPO in crop plants as well as the uptake and metabolism of iodosalicylates in lettuce have not yet been studied. This studyaimed to determine the effect of V on the uptake and accumulation of various forms of I, the metabolism of iodosalicylates and iodobenzoates and, finally, on the accumulation of T3 (triiodothyronine—as example of PDTHA) in plants. Lettuce (Lactuca sativa L. var. capitata ‘Melodion’ cv.) cultivation in a hydroponic NutrientFilm Technique (NFT) system was conducted with the introduction of 0 (control), 0.05, 0.1, 0.2, and 0.4 µM V doses of ammonium metavanadate (NH4VO3) in four independent experiments. No iodine treatment was applied in Experiment No. 1, while iodine compounds were applied at a dose of 10 µM (based on our own previous research) as KIO3, 5-iodosalicylic acid (5-ISA) and 3,5-diiodosalicylic acid (3,5-diISA) in Experiment Nos. 2, 3 and 4, respectively. When lettuce was grown at trace amount of I in the nutrient solution, increasing doses of V contributed to the increase of (a) I content in roots, (b) I uptake by whole lettuce plants (leaves + roots), and (c) vHPO activity in leaves (for doses 0.05–0.20 µM V). Vanadium was mainly found in roots where the content of this element increased proportionally to its dose. The content of V in leaves was not modified by V introduced into the nutrient solution. We found that5-ISA, 3,5-diISA and T3 were naturally synthesized in lettuce and its content increased when 5-ISA, 3,5-diISA were applied. Quantitative changes in the accumulation of organic metabolites (iodosalicylates and iodobenzoates) accumulation were observed, along with increased T3 synthesis, with its content in leaves exceeding the level of individual iodosalicylates and iodobenzoates. The content of T3 was not affected by V fertilization. It was concluded that iodosalicylates may participate in the biosynthesis pathway of T3—and probably of other PDTHA compounds.

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