Physiological and molecular responses to calcium supplementation inMicrocystis aeruginosa(Cyanobacteria)

Abstract

Calcium is an important element in water bodies that plays a pivotal role in numerous biological processes; however, its effects on bloom-forming cyanobacteria have been studied only rarely. In the present study, the effects of calcium on Microcystis aeruginosa, a major bloom-forming cyanobacterium, were investigated. Significant decreases in growth, chlorophyll a and maximum electron transport rate were shown when calcium was absent, while similar reductions in these parameters were also found at high concentrations of calcium (240 mg/l). The expression of psbA, grpE and recA was up-regulated significantly for 0 and 240 mg/l calcium treatments. The activity of catalase (CAT) also increased remarkably under these two treatments, suggesting that Microcystis suffered from stress under both calcium absence and under high calcium concentrations. Additionally, the polysaccharide synthesis gene, epsL, was up-regulated at high concentrations of calcium. These data suggest that calcium plays an important role in the growth of Microcystis, and that enhancement in polysaccharide synthesis in response to increases in calcium concentration might be responsible for bloom formation.

Role of calcium in the mitigation of heat stress in the cyanobacterium Anabaena PCC 7120

“…Studies of photosynthesis in the unicellular cyanobacterium Synechocystis at varying temperatures showed a certain extent of heat tolerance in PSII (Inoue et al, 2001). Recently, physiological and molecular responses to calcium supplementation in a bloom-forming cyanobacterium, Microcystis aeruginosa, revealed decreased growth and electron transfer rate in the absence of calcium (Shi et al, 2013).…”

Effects of seasonal variations and pond age on trace elements and their correlations with plankton productivity in commercial freshwater crayfish ( cherax cainii austin, 2002) earthen ponds

“…In a study by Castillo‐Soriano, Ibarra‐Junquera, Olivos‐Ortiz, Barragán‐Vázquez, and Meyer‐Willere (), chlorophyll a was negatively correlated with the Ca concentration in intensive culture of white leg shrimp ( Litopenaeus vannamei ). More research is needed to clarify the impacts of Ca on different aspects of primary production (Shi et al, ).…”

“…In the case of the marron ponds, the limestone was added only into the new ponds at the start of ponds utilization. (Shi et al, 2013).…”

“…Several researchers have explained the importance of trace elements in plankton growth and their role in photosynthesis (Anderson, Vinikour, & Brower, 1978;Egna & Boyd, 1997;Goldman, 2010;Kenneth, John, & David, 1991;Twining & Baines, 2013;Zhihong, Shiguang, & Xin, 2010). Trace element concentration can influence the plankton productivity in aquatic ecosystems (Giordano, Norici, & Hell, 2005;Giordano & Prioretti, 2016;Goldman, 2010;Ikem & Adisa, 2011;Jeziorski et al, 2008;Shi, Wu, & Song, 2013;Wallen, 1979). Moreover, their fluctuations can affect the phytoplankton (Downs, Schallenberg, & Burns, 2008;Zhang et al, 2013).…”

Using a Microfluidic Gradient Generator to Characterize BG-11 Medium for the Growth of Cyanobacteria Synechococcus elongatus PCC7942

“…This result may indicate the non-essentiality of these ingredients for cell growth, or for certain cases such as calcium and iron, maybe only a minute quantity possibly found in the water or chemical impurity is necessary for normal growth. Both calcium and iron are crucial elements required for the activity of signal transduction [27], electron transport in the photosystems [28], and certain classes of enzymes with Fe-S clusters. Iron is of particular importance for photosynthetic microorganisms such as cyanobacteria due to its binding to the thylakoid protein complexes for electron flow [28].…”