Effects of elevated pressure on Pseudanabaena galeata Böcher in varying light and dark environments
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To understand the effect of the hydrostatic pressure on Pseudanabaena galeata Böcher cells in both stratified and frequently mixed lakes, separate laboratory-scale models were developed. The pressure conditions in the stratified and mixed lakes were simulated in those models, and the variations of the cell and chlorophyll-a (Chl-a) concentration were analyzed. It was observed that an increase in pressure and darkness significantly reduced the cell concentration and pigmentation in P. galeata (p < 0.01, n = 3). After 10 days, the cell concentrations of P. galeata that were grown under conditions of a water depth of 30 m were reduced by 7.0%, per day, while the cell concentration rate after 10 days in atmospheric conditions was increased by 2.53% per day. During the experiment, cells were subjected to the prolonged darkness under 0.3 MPa pressure for 10 days and then exposed to the white light under atmospheric pressure for 5 days. Even after running this cycle for 60 days, 19.5% of the initial cells could survive. This rate exceeded the cell concentration-increasing rate in the control. These findings indicate that P. galeata has an adequate tolerance to pressure and fluctuating light irradiance and that the cells are able to propagate after escaping from those stress conditions.
KeywordsCyanobacteria Hydrostatic pressure Pseudanabaena galeata Böcher Prolonged darkness Chlorophyll-a Cell concentration
This study was financially supported by the River Foundation and a Grant-in-Aid from the Japan Society for the Promotion of Science (15K14038, 24656292).
- Abeynayaka, H D L, Asaeda T, and Kaneko Y 2017 Buoyancy limitation of filamentous cyanobacteria under prolonged pressure due to the gas vesicles collapse. Environ Manag:1–11Google Scholar
- Campbell D, Hurry V, Clarke AK, Gustafsson P, Öquist G (1998) Chlorophyll fluorescence analysis of cyanobacterial photosynthesis and acclimation. Microbiol Mol Biol Rev 62:667–683Google Scholar
- Kakimoto M, Ishikawa T, Miyagi A, Saito K, Miyazaki M, Asaeda T, Yamaguchi M, Uchimiya H, Kawai-Yamada M (2014) Culture temperature affects gene expression and metabolic pathways in the 2-methylisoborneol-producing cyanobacterium Pseudanabaena galeata. J Plant Physiol 171:292–300CrossRefGoogle Scholar
- Komárek J, Anagnostidis K (2011) Cyanoprokaryota part 2: Oscillatoriales. Spektrum Akademischer Verlag, Germany ISBN 6070225651Google Scholar
- Rippka R (1979) Generic assignments, strain histories, and properties of pure cultures of cyanobacteria. J Gen Microbiol 111:1–61Google Scholar
- Sivonen K (1990) Effects of light, temperature, nitrate, orthophosphate, and bacteria on growth of and hepatotoxin production by Oscillatoria agardhii strains. Appl Environ Microbiol 56:2658–2666Google Scholar
- Visser P, Ibelings B, Bormans M, and Huisman J (2015) Artificial mixing to control cyanobacterial blooms: a review. Aquat Ecol:1–19Google Scholar
- Wef A A (1998) Standard methods for the examination of water and wastewater. Washington, DCGoogle Scholar