scholarly journals Features of cell metabolism of Chlamydomonas reinhardtii CC-124 wild strain [137c] under mixotrophic and phototrophic cultivation

Algologia ◽  
2016 ◽  
Vol 26 (1) ◽  
pp. 33-45
Author(s):  
O.V. Sytar ◽  
◽  
O.P. Olkhovych ◽  
O.V. Karaushu ◽  
R. Storandt ◽  
...  
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Cell Metabolism ◽  
Wild Strain ◽  
Strain 137C

Features of Cell Metabolism of Chlamydomonas reinhardtii CC-124 Wild Strain [137c] Under Mixotrophic and Phototrophic Cultivation

2015 ◽  
Vol 17 (4) ◽  
pp. 371-384
Author(s):  
O.V. Sytar ◽  
O. P. Olkhovich ◽  
O.V. Karaushu ◽  
R. Storandt ◽  
P. Waldeck ◽  
...  
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Cell Metabolism ◽  
Wild Strain ◽  
Strain 137C

Cellular Photosynthetic Rate of Fully and Partially Pigmented Chlamydomonas reinhardtii as a Function of Irradiance

2011 ◽  
Author(s):  
Thomas E. Murphy ◽  
Halil Berberog˘lu
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Green Algae ◽  
Photosynthetic Rate ◽  
Wild Strain ◽  
Experimental Setup ◽  
Light Penetration ◽  
Photosynthetic Rates ◽  
Planktonic Algae ◽  
Mass Cultures ◽  
Increase Productivity

This paper reports the cellular photosynthetic rates of the green algae Chlamydomonas reinhardtii wild strain and its truncated chlorophyll antenna transformant, tla1, as a function of local irradiance. It is hypothesized that reduction in the pigmentation of algae cells can enhance light peneration in mass cultures and increase productivity. Thus, an experimental setup was designed to expose each cell within planktonic algae cultures to a nearly uniform irradiance. An oxygen microsensor was used to monitor the photosynthetic rate as the irradiance onto the sample was varied. The results showed that the cellular photosynthetic rate of the wild strain, CC125, was greater than that of tla1 at all irradiances, by a factor that ranged from 1.7 to 4. Photoinhibition was observed in both strains, although the effect was more pronounced in CC125. Although less pigmented cells enable deeper light penetration in photobioreactors, their reduced phosotynthetic rate can negate this benefit.

scholarly journals Trehalose-6-phosphate links singlet oxygen-induced signalling with metabolic signalling in Chlamydomonas reinhardtii

2021 ◽  
Author(s):  
Waeil Al Youssef ◽  
Regina Feil ◽  
Maureen Saint-Sorny ◽  
Xenie Johnson ◽  
John E. Lunn ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Chlamydomonas Reinhardtii ◽  
Tricarboxylic Acid Cycle ◽  
Cell Metabolism ◽  
Tca Cycle ◽  
Tricarboxylic Acid ◽  
Metabolic Signalling ◽  
Retrograde Signalling ◽  
Essential Components ◽  
Genes Encoding

Singlet oxygen (1O2) induces retrograde signalling in chloroplasts. Using a novel mutant screen, we identified a mutation in the TREHALOSE-6-PHOSPHATE PHOSPHATASE 1 (T6PP1) gene that results in accumulation of trehalose 6-phosphate, a reprogramming of cell metabolism, and impairment of 1O2-induced retrograde signalling in Chlamydomonas reinhardtii. From transcriptomic analysis and metabolite profiling, we conclude that accumulation or deficiency of certain metabolites directly affect 1O2-signalling. 1O2-inducible GLUTATHIONE PEROXIDASE 5 (GPX5) gene expression is suppressed by increased content of fumarate, an intermediate in the tricarboxylic acid cycle (TCA cycle) in mitochondria and dicarboxylate metabolism in the cytosol, while it is promoted by another TCA cycle intermediate, aconitate. Furthermore, genes encoding known essential components of chloroplast-to-nucleus 1O2-signalling show decreased transcript levels in a t6pp1 mutant, which can be rescued by exogenous application of aconitate. We demonstrate that chloroplast retrograde signalling involving 1O2 depends on mitochondrial and cytosolic processes and that the metabolic status of the cell determines the response to 1O2.

Ultrastructure of Chlamydomonas reinhardtii following exposure to paraquat: comparison of wild type and a paraquat-resistant mutant

1993 ◽  
Vol 71 (1) ◽  
pp. 174-182 ◽  
Author(s):  
Douglas F. Bray ◽  
John R. Bagu ◽  
Kazuo Nakamura
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Wild Type Strain ◽  
Single Gene ◽  
Resistant Mutant ◽  
Cross Resistance ◽  
Wild Type ◽  
Ultrastructural Examination ◽  
Unicellular Green Alga ◽  
Strain 137C ◽  
Mutant Cells

A mutant (NL-51) of the unicellular green alga Chlamydomonas reinhardtii Dangeard isolated from a wild-type strain (137c+) was shown to be resistant to the bipyridilium herbicide paraquat at the concentration at which growth of the wild type was inhibited. Tetrad analysis from a cross between the mutant and the wild type showed 2:2 segregation, indicating that the resistance is under control of a single gene. Cross-resistance of the mutant to methionine and to methionine combined with riboflavin suggested that the resistance is due to increased levels of one of the enzymes capable of detoxifying active oxygens. Ultrastructural examination of mutant and wild-type cells exposed to paraquat revealed that the mutant cells were 3 to 4 times more resistant, but both strains showed the same sequence of deterioration. Damage was first manifested as swelling of the mitochondria and dilation of the perinuclear space. This was followed by disintegration of the nuclear matrix and the chloroplast thylakoids. Key words: Chlamydomonas reinhardtii, methionine resistance, paraquat, paraquat-resistant mutant, ultrastructure.

Heterogeneity in endogenous amino acid pools of Chlamydomonas reinhardtii and C. eugametos

1991 ◽  
Vol 69 (6) ◽  
pp. 1194-1198 ◽  
Author(s):  
James E. Thomas ◽  
Christine A. Goertzen ◽  
Kazuo Nakamura
Keyword(s):  
Amino Acid ◽  
Chlamydomonas Reinhardtii ◽  
Growth Patterns ◽  
Apparent Difference ◽  
Mating Types ◽  
Chlamydomonas Eugametos ◽  
Unicellular Green Alga ◽  
Mendelian Gene ◽  
Strain 137C ◽  
Endogenous Amino Acid

Levels of endogenous amino acid pools were measured for two species of the unicellular green alga Chlamydomonas. In C. reinhardtii, opposite mating types, designated + and −, of strain 137c were examined. The soluble pool of glutamic acid was most abundant in strain 137c−. In strain 137c+ similar levels of this amino acid were present, and high levels of cystine were observed. A soluble pool for the amino acid methionine was not detected in either strain. In opposite mating types of C. eugametos (strain Nos. 9 and 10), a soluble pool of alanine was most abundant, whereas neither cystine nor methionine were detected. When C. reinhardtii strain 137c+ was grown in the dark, cystine was not detectable, and proline markedly increased. Similarly, growth of strain 137c+ on nitrogen-deficient medium supplemented with a limited amount of arginine as a nitrogen source resulted in an apparent disappearance of pools of cystine. No apparent difference in the growth patterns of strains 137c+ and 137c− was observed. Tetrad analysis indicates that the high cystine content found in strain 137c+ is neither a characteristic of mating type nor under control of a single Mendelian gene. Key words: Chlamydomonas reinhardtii, Chlamydomonas eugametos, amino acid pool, cystine.

METABOLISM AND MODE OF ACTION OF ANDROGENS IN TARGET TISSUES OF MALE RATS

1972 ◽  
Vol 69 (1) ◽  
pp. 165-173 ◽  
Author(s):  
H. Schmidt ◽  
I. Noack ◽  
K. D. Voigt
Keyword(s):  
Cell Proliferation ◽  
Cell Metabolism ◽  
Seminal Vesicles ◽  
Male Rats ◽  
Ventral Prostate ◽  
Nucleic Acid Content ◽  
The Difference ◽  
Independent Effects ◽  
Sites Of Action ◽  
Peripheral Metabolism

ABSTRACT The effect of testosterone and 5α-dihydrotestosterone on protein and nucleic acid content as well as on the activities of some enzymes has been studied in the ventral prostate and the seminal vesicles of immature castrated rats. Both androgens were given intraperitoneally in doses of 1 mg daily for one or three days the rats were sacrificed one day after the last injection. In the prostate it was found that 5α-dihydrotestosterone had a greater effect on DNA increase, i. e. cell proliferation than testosterone, whereas cell metabolism was stimulated by the two androgens to nearly the same extent. In the seminal vesicles a single dose led to the same results as had been obtained in the prostate, i. e. a greater cell proliferative action of 5α-dihydrotestosterone and an equal stimulation of cell metabolism by testosterone and 5α-dihydrotestosterone was also observed. When three doses of the two androgens were given, cell proliferation as well as cell metabolism in the seminal vesicles were significantly more increased after 5α-dihydrotestosterone than after testosterone. The difference of action after systemic administration of the two androgens is explained by their different accumulation and by their different peripheral metabolism in the target tissues. From the partly independent effects of various androgens on cell proliferation and cell metabolism the conclusion may be drawn that there exist at least two intracellular sites of action.

Antagonistic activity of Bacillus subtilis strains isolated from various sources

2018 ◽  
Vol 8 (2) ◽  
pp. 354-364
Author(s):  
A. N. Irkitova ◽  
A. V. Grebenshchikova ◽  
A. V. Matsyura
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Wild Strain ◽  
Fish Farming ◽  
Antagonistic Activity ◽  
Antagonistic Effect ◽  
E Coli ◽  
Long Period ◽  
Test Culture ◽  
Agar Media

<p>An important link in solving the problem of healthy food is the intensification of the livestock, poultry and fish farming, which is possible only in the adoption and rigorous implementation of the concept of rational feeding of animals. In the implementation of this concept required is the application of probiotic preparations. Currently, there is an increased interest in spore probiotics. In many ways, this can be explained by the fact that they use no vegetative forms of the bacilli and their spores. This property provides spore probiotics a number of advantages: they are not whimsical, easily could be selected, cultivated, and dried. Moreover, they are resistant to various factors and could remain viable during a long period. One of the most famous spore microorganisms, which are widely used in agriculture, is <em>Bacillus subtilis</em>. Among the requirements imposed to probiotic microorganisms is mandatory – antagonistic activity to pathogenic and conditional-pathogenic microflora. The article presents the results of the analysis of antagonistic activity of collection strains of <em>B. subtilis</em>, and strains isolated from commercial preparations. We studied the antagonistic activity on agar and liquid nutrient medias to trigger different antagonism mechanisms of <em>B. subtilis</em>. On agar media, we applied three diffusion methods: perpendicular bands, agar blocks, agar wells. We also applied the method of co-incubating the test culture (<em>Escherichia coli</em>) and the antagonist (or its supernatant) in the nutrient broth. Our results demonstrated that all our explored strains of <em>B. subtilis</em> have antimicrobial activity against a wild strain of <em>E. coli</em>, but to varying degrees. We identified strains of <em>B. subtilis</em> with the highest antagonistic effect that can be recommended for inclusion in microbial preparations for agriculture.</p><p><em><br /></em><em></em></p>

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