scholarly journals Competitive dominance of Microcystis aeruginosa against Raphidiopsis raciborskii is strain- and temperature-dependent

2020 ◽  
pp. 36
Author(s):  
Lamei Lei ◽  
Jingjun Dai ◽  
Qiuqi Lin ◽  
Liang Peng
Keyword(s):  
Microcystis Aeruginosa ◽  
Competitive Ability ◽  
Competitive Exclusion ◽  
Strain Difference ◽  
Freshwater Ecosystems ◽  
Cylindrospermopsis Raciborskii ◽  
Temperature Dependent ◽  
Temperature Levels ◽  
Multiple Strains ◽  
Allelopathic Interactions

Microcystis aeruginosa and Raphidiopsis raciborskii (previously Cylindrospermopsis raciborskii) are both common bloom-forming cyanobacteria which can coexist but alternatively dominate in freshwater ecosystems. To predict their blooming dynamics, we need to understand the potential environmental factors determining their succession. In the present study, we examined the pairwise competition of the three M. aeruginosa strains (FACHB905, 469 and 915) with one R. raciborskii strain (N8) at three temperature levels (16 °C, 24 °C, and 32 °C). We found that the competitive ability of three Microcystis strains were highly variable. M. aeruginosa FACHB905 was the strongest competitor among them which can finally exclude R. raciborskii N8 regardless of initial biovolume ratios and temperature levels. The competitive exclusion of N8 by 915 also was observed at 24 °C, but they coexisted at 16 °C and 32 °C. We observed that M. aeruginosa FACHB469 and R. raciborskii N8 were able to coexist under all the temperature levels, and M. aeruginosa FACHB469 was the weakest competitor among the three M. aeruginosa strains. Rates of competitive exclusion (RCE) showed that temperature affects the competition between three M. aeruginosa strains and R. raciborskii N8. M. aeruginosa strains always grew quickly at 24 °C and significantly enlarged its dominance in the co-culture system, while R. raciborskii N8 was able to maintain its initial advantages at both 16 and 32 °C. The competitive advantage of M. aeruginosa FACHB905 may be explained by allelopathic interactions through its allelochemicals and other secondary metabolites other than microcystin. We concluded that both strain difference and temperature can affect the competition between M. aeruginosa and R. raciborskii. Our results highlighted the complexity of cyanobacterial dynamics in waterbodies where there exist multiple strains.

scholarly journals Allelopathic interactions of linoleic acid and nitric oxide increase the competitive ability of Microcystis aeruginosa

2017 ◽  
Vol 11 (8) ◽  
pp. 1865-1876 ◽  
Author(s):  
Hao Song ◽  
Michel Lavoie ◽  
Xiaoji Fan ◽  
Hana Tan ◽  
Guangfu Liu ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Linoleic Acid ◽  
Microcystis Aeruginosa ◽  
Competitive Ability ◽  
Allelopathic Interactions

scholarly journals Evidence of Quorum Sensing in Cyanobacteria by Homoserine Lactones: The Origin of Blooms

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1831
Author(s):  
Natalia Herrera ◽  
Fernando Echeverri
Keyword(s):  
Cell Proliferation ◽  
Quorum Sensing ◽  
Microcystis Aeruginosa ◽  
Industrial Effluents ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Bacterial Communication ◽  
Homoserine Lactones ◽  
Exogenous Compounds ◽  
Almost All

Although several theories have been postulated to explain cyanobacterial blooms, their biochemical origin has not yet been found. In this work, we explore the existence of bacterial communication, called quorum sensing, in Microcystis aeruginosa and Cylindrospermopsis raciborskii. Thus, the application of several known acylhomoserine lactones to cultures of both cyanobacteria causes profound metabolic. At 72 h post-application, some of them produced substantial increases in cell proliferation, while others were inhibitors. There was a correlation with colony-forming activity for most of them. According to ELISA analysis, the microcystin levels were increased with some lactones. However, there was a clear difference between M. aeruginosa and C. raciborskii culture since, in the first one, there was an inducing effect on cell proliferation, while in C. raciborskii, the effects were minor. Besides, there were compound inhibitors and inducers of microcystins production in M. aeruginosa, but almost all compounds were only inducers of saxitoxin production in C. raciborskii. Moreover, each lactone appears to be involved in a specific quorum sensing process. From these results, the formation of cyanobacterial blooms in dams and reservoirs could be explained since lactones may come from cyanobacteria and other sources as bacterial microflora-associated or exogenous compounds structurally unrelated to lactones, such as drugs, industrial effluents, and agrochemicals.

scholarly journals Harmful phytoplankton blooms and fish mortality in a eutrophicated reservoir of northeast Brazil

2008 ◽  
Vol 51 (4) ◽  
pp. 633-641 ◽  
Author(s):  
Naithirithi Tiruvenkatachary Chellappa ◽  
Sarah Laxhmi Chellappa ◽  
Sathyabama Chellappa
Keyword(s):  
Cyanobacterial Bloom ◽  
Hplc Method ◽  
Freshwater Ecosystems ◽  
Cyanobacterial Blooms ◽  
Fish Mortality ◽  
Cylindrospermopsis Raciborskii ◽  
Northeast Brazil ◽  
Cyanobacterial Toxin ◽  
Bloom Formation ◽  
Harmful Effects

The aim of this work was to study the eutrophication in the tropical freshwater ecosystems and the consequent cyanobacterial bloom formation and economical damage to fisheries and harmful effects to public health. Mass fish mortality due to toxin producing cyanobacterial blooms was registered during December 2003 in Marechal Dutra Reservoir, Acari/RN, Northeast Brazil. Phytoplankton and fish samplings were carried out on alternate days during the episode of fish mortality and monthly during January to June 2004. The cyanobacterial toxin was identified and quantified from the seston samples and liver of the dead fishes using the standard HPLC method. The results indicated that the toxic blooms of Cylindrospermopsis raciborskii and Microcystis aeruginosa were persistent for two weeks and represented 90% of the phytoplankton species assemblages. The lethally affected fishes were Oreochromis niloticus, Plagioscion squamosissimus, Cichla monoculus, Prochilodus brevis, Hoplias malabaricus and Leporinus friderici. The microcystin levels varied from 0.07 to 8.73µg L-1 the seston samples and from 0.01 to 2.59µg g-1in the liver samples of the fishes during the bloom period.

scholarly journals Spatiotemporal Variations in Microcystin Concentrations and in the Proportions of Microcystin-Producing Cells in Several Microcystis aeruginosa Populations

2010 ◽  
Vol 76 (14) ◽  
pp. 4750-4759 ◽  
Author(s):  
M. Sabart ◽  
D. Pobel ◽  
E. Briand ◽  
B. Combourieu ◽  
M. J. Salençon ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Environmental Conditions ◽  
Real Time Pcr ◽  
Geographical Area ◽  
Freshwater Ecosystems ◽  
Cyanobacterial Blooms ◽  
Spatiotemporal Variations ◽  
Potential Toxicity ◽  
Genotype Composition ◽  
Over Time

ABSTRACT With the aim of explaining the variations in microcystin (MC) concentrations during cyanobacterial blooms, we studied several Microcystis aeruginosa populations blooming in different freshwater ecosystems located in the same geographical area. As assessed by real-time PCR, it appeared that the potentially MC-producing cells (mcyB +) were predominant (70 to 100%) in all of these M. aeruginosa populations, with the exception of one population in which non-MC-producing cells always dominated. Apart from the population in the Grangent Reservoir, we found that the proportions of potentially MC-producing and non-MC-producing cells varied little over time, which was consistent with the fact that according to a previous study of the same populations, the intergenic transcribed spacer (ITS) genotype composition did not change (38). In the Grangent Reservoir, the MC-RR variant was the dominant microcystin variant throughout the bloom season, despite changes in the ITS composition and in the proportions of mcyB + cells. Finally, the variations in total MC concentrations (0.3 to 15 μg liter−1) and in the MC cellular quotas (0.01 to 3.4 pg cell−1) were high both between and within sites, and no correlation was found between the MC concentrations and the proportion of mcyB + cells. All of these findings demonstrate that very different results can be found for the proportions of potentially MC-producing and non-MC-producing cells and MC concentrations, even in M. aeruginosa populations living in more or less connected ecosystems, demonstrating the importance of the effect of very local environmental conditions on these parameters and also the difficulty of predicting the potential toxicity of Microcystis blooms.

scholarly journals Warmer temperatures interact with salinity to weaken physiological facilitation to stress in freshwater fishes

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Richard H Walker ◽  
Geoffrey D Smith ◽  
Spencer B Hudson ◽  
Susannah S French ◽  
Annika W Walters
Keyword(s):  
Stress Reactivity ◽  
Multiple Stressors ◽  
Cutthroat Trout ◽  
Freshwater Fishes ◽  
Freshwater Ecosystems ◽  
Negative Effects ◽  
Temperature Dependent ◽  
Glucose Levels ◽  
Baseline Concentrations ◽  
Underlying Mechanisms

Abstract Management of stressors requires an understanding of how multiple stressors interact, how different species respond to those interactions and the underlying mechanisms driving observed patterns in species’ responses. Salinization and rising temperatures are two pertinent stressors predicted to intensify in freshwater ecosystems, posing concern for how susceptible organisms achieve and maintain homeostasis (i.e. allostasis). Here, glucocorticoid hormones (e.g. cortisol), responsible for mobilizing energy (e.g. glucose) to relevant physiological processes for the duration of stressors, are liable to vary in response to the duration and severity of salinization and temperature rises. With field and laboratory studies, we evaluated how both salinity and temperature influence basal and stress-reactive cortisol and glucose levels in age 1+ mottled sculpin (Cottus bairdii), mountain sucker (Catostomus platyrhynchus) and Colorado River cutthroat trout (Oncorhynchus clarki pleuriticus). We found that temperature generally had the greatest effect on cortisol and glucose concentrations and the effect of salinity was often temperature dependent. We also found that when individuals were chronically exposed to higher salinities, baseline concentrations of cortisol and glucose usually declined as salinity increased. Reductions in baseline concentrations facilitated stronger stress reactivity for cortisol and glucose when exposed to additional stressors, which weakened as temperatures increased. Controlled temperatures near the species’ thermal maxima became the overriding factor regulating fish physiology, resulting in inhibitory responses. With projected increases in freshwater salinization and temperatures, efforts to reduce the negative effects of increasing temperatures (i.e. increased refuge habitats and riparian cover) could moderate the inhibitory effects of temperature-dependent effects of salinization for freshwater fishes.

scholarly journals Long‐term acclimation might enhance the growth and competitive ability of Microcystis aeruginosa in warm environments

2021 ◽  
Author(s):  
Bogdan Drugă ◽  
Elisabeth Ramm ◽  
Edina Szekeres ◽  
Cecilia Chiriac ◽  
Adriana Hegedüs ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Competitive Ability

scholarly journals SIZE EFFECT OF COPPER NANOPARTICALS ON MICROCYSTIS AERUGINOSA

2018 ◽  
Vol 16 (2) ◽  
pp. 361-367
Author(s):  
Nguyen Trung Kien ◽  
Tran Thi Thu Huong ◽  
Nguyen Hoai Chau ◽  
Dang Dinh Kim ◽  
Duong Thi Thuy
Keyword(s):  
Particle Size ◽  
Microcystis Aeruginosa ◽  
Copper Nanoparticles ◽  
Algal Blooms ◽  
Water Environment ◽  
Freshwater Ecosystems ◽  
Particle Sizes ◽  
Toxic Cyanobacteria ◽  
The Stability ◽  
Effect Of Copper

Cyanobacterial and toxins produced in cyanobacterial water blooms cause serious environmental problems which effects on freshwater ecosystems. The use of nanomaterials to control algal blooms is a new potential way for practical application due to its antibacterial as well as distinct physicochemical properties of nanomaterials. The particle size is one of the most determinant characteristics creating the different between nanomaterials and their larger bulk counterparts. However, size-dependent toxicity of nanoparticles has remained largely unknown. This study aimed to evaluate effect of three different nanoparticle sizes (d ≤ 10 nm; 30 nm ≤ d ≤ 40 nm and d ≥ 50 nm) on toxic cyanobacteria Microcystis aeruginosa. The copper nanoparticles were synthesized by electrochemical method and coated with chitosan to enhance the stability of materials in the water environment. The copper nanoparticle concentrations selected for toxic test were range from 0 (control); 0,01ppm; 0,05ppm; 0,1 ppm; 1ppm and 5 ppm. After ten days of experiment, the growth of M. aeruginosa was mainly affected at concentrations of 1 ppm and 5 ppm and there are no differences in inhibition between the particle sizes with efficiency of more than 80% in comparison to control. The highest toxicity of copper nanoparticles in M. aeruginosa was observed at particle size of 30 nm ≤ d ≤ 40 nm with EC50 = 0,73 ppm, which was respectively three to seven times less than the particle sizes of d ≥ 50 nm (EC50 = 2,62 ppm) and d ≤ 10nm (EC50 = 5,02 ppm) at the same time.

Sign in / Sign up

Export Citation Format

Share Document