Glutamine synthetases (GSs) from two cyanobacteria, one unicellular (Synechocystis sp. strain PCC 6803) and the other filamentous (Calothrix sp. strain PCC 7601 [Fremyella diplosiphon]), were purified to homogeneity. The biosynthetic activities of both enzymes were strongly inhibited by ADP, indicating that the energy charge of the cell might regulate the GS activity. Both cyanobacteria exhibited an ammonium-mediated repression of GS synthesis. In addition, the Synechocystis sp. showed an inactivation of GS promoted by ammonium that had not been demonstrated previously in cyanobacteria.
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http://dx.doi.org/10.1128/jb.172.8.4732-4735.1990 | DOI Listing |
RSC Chem Biol
January 2025
Department of Chemical and Biological Engineering, University of Wisconsin - Madison Madison Wisconsin 53706 USA
Cyanobacteria are widespread, photosynthetic, gram-negative bacteria that generate numerous bioactive secondary metabolites complex biosynthetic enzymatic machinery. The model cyanobacterium sp. strain PCC 7002, hereafter referred to as PCC 7002, contains a type I polyketide synthase (PKS), termed olefin synthase (OlsWT), that synthesizes 1-nonadecene and 1,14-nonadecadiene: α-olefins that are important for growth at low temperatures.
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January 2025
Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Cyanobacteria are advantageous hosts for industrial applications toward achieving sustainable society due to their unique and superior properties such as atmospheric CO fixation via photosynthesis. However, cyanobacterial productivities tend to be weak compared to heterotrophic microbes. To enhance them, it is necessary to understand the fundamental metabolic mechanisms unique to cyanobacteria.
View Article and Find Full Text PDFHeliyon
January 2025
Functional Omics and Bioprocess Development Laboratory, Institute of Biological Sciences, Faculty of Science, Universiti Malaya, Kuala Lumpur, 50603, Malaysia.
Eutrophication and hypereutrophication in lakes foster harmful blue-green algal blooms, which pose a significant threat to the ecological health of freshwater reservoirs. This study investigated the effectiveness of the bio-flocculation approach using the fungus strain BGF4A1 to remove these harmful blooms, specifically targeting cyanobacterial species like PCC-7914. Key flocculation parameters, cyanobacterial concentrations, adsorption kinetics, and pellet morphology were explored in this research.
View Article and Find Full Text PDFMicrobiol Res
January 2025
National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China. Electronic address:
RNase III, a ubiquitously distributed endonuclease, plays an important role in RNA processing and functions as a global regulator of gene expression. In this study, we explored the role of RNase III in mediating the oxidative stress response in Synechocystis sp. PCC 6803.
View Article and Find Full Text PDFBioresour Technol
December 2024
Microalgal Biotechnology Laboratory, The French Associates Institute for Agriculture and Biotechnology of Drylands, The J. Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000, Israel. Electronic address:
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