Seminars
Seminars of the Institute of Hydrobiology BC CAS
17.10.2019
The picocyanobacterium Synechococcus spp.: its ecological success and adaptation strategies
Cristiana Callieri
Affiliation: CNR, Italy
Annotation: Cyanobacteria are among the oldest autotrophic organisms on Earth, and have contributed to shaping the planet's biogeochemistry with their significant biomass and key metabolic activities. Synechococcus, is one of the prevalent genera in the order Chroococcales, common in oceans and lakes and is characterized by a small size (around 2 µm) and a coccoid unicellular or microcolony morphology. This tiny cell is photoautotrophic, thus possessing all the machinery for photosynthesis, and even accessory pigments to capture light at different wavelengths, allowing the organism to adapt to different underwater light conditions. However, even the deeper hypolimnion or mesopelagic zone of the sea, it shows remarkable cell abundances, offering evidence for the survival of the genus even without light, in harsh conditions, likely relying on heterotrophic or fermentation metabolism. Even if Synechococcus spp. are more abundant in temperate waters, the adaptation to low temperatures and to long periods of darkness provides evidence for the extreme plasticity of this picocyanobacteria. Here I will present the recent finding of one Synechococcus spp. adaptability to live in the deep anoxic Black Sea, showing the disparate strategies used by Synechococcus to adapt to environmental changes that could have ensured the ubiquitous presence of this genus during Earth's evolution.
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14.11.2019
Modelling the seasonally varying effects of environmental factors on phytoplankton concentrations in temperate reservoirs
Ma. Cristina Paule-Mercado
Affiliation: Biology Centre CAS, Institute of Hydrobiology
Annotation: Over the past three decades, studies have attempted to use the CE-QUAL-W2, a 2D hydrodynamics and water quality model, with constant algae/chl-a ratio (ACHLA) in order to predict the occurrence of algal bloom in the waterbodies. In natural setting, the phytoplankton concentrations may change according to food web dynamics, seasons, and temperature in the reservoir. In this seminar, will discuss the integration of CE-QUAL-W2 and modified ACHLA in order to improve the phytoplankton prediction in the Římov reservoir.
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28.11.2019
Bioactive cyanobacterial lipopeptides: genome mining, detection, and structure-activity relationships
Jan Mareš
Affiliation: Biology Centre CAS, Institute of Hydrobiology
Annotation: Summary of the project successfully finished in 2018.
If not otherwise stated, seminars take place Thursdays at 13:00 h in the Lecture hall IHB institute, Na Sádkách 7 (the "big lecture hall" at the 1-st floor, 008). All seminars are given in English. Contact: Jiří Kaňa, e-mail: jiri.kana@hbu.cas.cz
