Reactive oxygen species in biological systems
We study the origin of radical and non-radical reactive oxygen species (ROS) in plant and animal cells. We focus on the mechanism and site of ROS generation, scavenging of ROS by enzymatic and non-enzymatic antioxidants, and investigating the deleterious effects of ROS on lipids (lipid peroxidation) and proteins (protein oxidation).
Team members: Shailja Bansal, Renu Kushwaha, Vendula Paculová, Pavel Pospíšil (vedoucí), Ankush Prasad, Marek Rác, Dipti Sonkar
Molecular and cellular pharmacology
The main research goal of our group is to deepen the knowledge and understanding of the mechanisms of biological (antitumor and antibiotic) action of metallopharmaceuticals and to use this expanded knowledge to develop new classes of metallopharmaceuticals with truly new mechanisms of action and new spectra of biomedical activity.
Team members: Petra Andršová, Michal, Berecka, Viktor Brabec (the head), Jana Kašpárková, Jitka Prachařová
Structure and function of protein complexes
Our research is focused on the isolation and structural and functional characterization of protein complexes using single particle (cryo) electron microscopy, electron tomography and image analysis. We focus our attention mainly on protein supercomplexes involved in photosynthesis in a wide range of organisms from cyanobacteria, diatoms, brown and green algae to land plants.
Team members: Gabriela Častulíková, Dominika Čmielová, Petr Ilík, Roman Kouřil (the head), Monika Opatíková, Tereza Vánská
Biophysical aspects of plant physiology
We study i) changes in plant functioning induced by stress and senescence by measuring in vivo chlorophyll fluorescence, plant water status, leaf optical properties and cell membrane stability, ii) electrical signals and their physiological responses in carnivorous plants and Arabidopsis thaliana, and iii) various aspects photosynthesis and its regulation also using a mathematical modeling.
Team members: David Fuente Herraiz, Martin Hřivňacký, Zuzana Kučerová, Dušan Lazár (the head), Jan Nauš, Ladislav Nedbal, Barbora Nosková, Andrej Pavlovič, Martina Špundová
With respect to the study of the regulation of photosynthesis, we are developing (Lazár, Nedbal) the methodology of the so-called forced oscillations; we illuminate the plant with light (input signal), the intensity of which changes as a sine function, and we monitor the response of the plant (output signal), e.g. by measuring the chlorophyll fluorescence, or other signals reflecting the function of photosynthesis (I830, P515). The output signal is forced to oscillate and due to the non-linearity of photosynthetic reactions the output oscillations are not a simple sine. With a suitable period (frequency) of the input signal, resonance (= tuning) with the given existing regulation mechanism can be achieved, which is reflected in the parameters of the output signal. By changing the period (frequency) of the input signal, we reveal/study individual regulatory mechanisms of photosynthesis. The importance of this approach is also related to the fact that plants are normally exposed to fluctuating light in nature (movement of leaves and the whole plant caused by wind, movement of clouds, etc.), when repeated regulation of photosynthetic processes is needed, in contrast to illumination the plant with light of constant intensity in standard laboratory measurements routinely used up to now.
Knowledge of the regulatory mechanisms of photosynthesis and their frequency dependence could in appropriate lighting lead to a greater efficiency of photosynthesis and thus to a greater productivity of plants.
We published the first results on this topic in renowned journals Plant Physiology, Journal of Experimental Botany, New Phytologist, Plant, Cell and Environment, and Plant Physiology and Biochemistry and we solve this topic also in a project with acronym DREAM funded by European Innovation Council of Horizon Europe program.
An example of experimental data is presented in the figure below, which shows courses of the output signals (Chl fluorescence, I830, P515) in dependence on the period T of input sine signal (incident light).
