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Application of diazotrophic cyanobacteria in plants biomass production

100%

Pszczolkowska A., Romanowska-Duda Z., Grzesik M., Pszczolkowski W.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 3

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A correlation matrix of alkaline phosphatase and sporulation in diazotrophic cyanobacteria and its thermo-tolerant mutant

100%

Pandey M., Tiwari D. N.

Polish Journal of Microbiology

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2004

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tom 53

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nr 4

Alkaline phosphatase (phosphomonoesterase i.e. PMEase) activity in heterocystous cyanobacteria Anabaena flos-aquae, Nostoc calcicola, Calothrix brevissima, Scytonema javanicum and Hapalosiphon intricatus is known to be temperature and pH dependent. Maximum level of enzyme activity was recorded at either 35°C or 37.5°C. Also, the cell bound phosphomonoesterase enzyme was shown to exhibit pH optima of 10.0 or 10.2. A thermo-tolerant (tr) mutant isolated after MNNG (N-methyl-N'-nitro-N-nitrosoguanidine) mutagenesis in Calothrix brevissima exhibited 10°C higher temperature optima and comparatively high pH optima (pH 10.4) for phosphomonoesterase enzyme. The mutant grew with a maximum growth rate (k) at 50°C. Activation energy (Ea) for cyanobacterial strains was in a narrow range between 45 to 52 kJ mol⁻¹. A little variation in temperature and pH optima was also observed in phosphomonoesterase activity of Calothrix brevissima and its thermo-tolerant mutant while utilizing various organic phosphates as substrate what indicated the substrate dependence temperature and pH optima. Cyanobacterial strains grown at their respective temperature and pH optima differentiated spores less frequently though, coupled with early initiation of spore.

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Nutrient modulated alkaline phosphatase and associated processes in diazotrophic cyanobacteria

80%

Pandey M.

Polish Journal of Microbiology

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2006

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tom 55

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nr 1

Nutrient regulation of alkaline phosphatase (Phosphomonoesterase - PMEase) was studied in some diazotrophic cyanobacterial strains like Anabaena variabilis, Anabaena torulosa, Calothrix brevissima, Scytonema javanicum and Hapalosiphon intricatus, in response to the macronutrients (Phosphate, Calcium and Magnesium) and the micronutrients (Zinc, Copper, Iron and Manganese). The phosphate grown cells of cyanobacterial strains when transferred to the phosphate deficient medium, showed expression of cellular PMEase activity and released the enzyme extracellularly. The increased concentration of phosphate inhibited enzyme activity severely in a concentration dependent manner. The phosphate depletion stimulated spore formation in A. variabilis and H. intricatus, whereas its addition enhanced spore's differentiation in A. torulosa. The switch-on time detected for both cellular and extracellular PMEase varies among the strains. The increase in ionic concentration of Ca²⁺ enhanced the PMEase activity more profoundly than Mg²⁺ in diazotrophic strains. The lower level of micronutrients either promoted or had no effect on photosynthetic inhibitors (DCMU) and respiratory electron transport chain inhibitor (sodium azide). It revealed that the energy for the synthesis of PMEase enzyme is mostly derived from photosynthesis and the role of respiratory energy is marginal. The Phosphate (Pi) uptake function in the strains was found to be substrate concentration dependent.

Ograniczanie wyników

2 Polish Journal of Microbiology

1 BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

2 Pandey M.

1 Grzesik M.

1 Pszczolkowska A.

1 Pszczolkowski W.

1 Romanowska-Duda Z.

1 Tiwari D. N.

1 2013

1 2006

1 2004

Application of diazotrophic cyanobacteria in plants biomass production

A correlation matrix of alkaline phosphatase and sporulation in diazotrophic cyanobacteria and its thermo-tolerant mutant

Nutrient modulated alkaline phosphatase and associated processes in diazotrophic cyanobacteria