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Reovirus replication factories as a new antimicrobial target
Grant agency: GACR
Identification number of grant: 22-25396S
Head of the project: RNDr. Roman Tůma (Jihočeská Universita v Českých Budějovicích, Přírodovědecká fakulta)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Viruses are pathogens causing epidemics and outbreaks with costly consequences. Antiviral drugs represent effective treatment and outbreak control but are usually specific for a virus. We explore formation of viral replication factories (VF) as potentially conserved mechanism among dsRNA viruses of the Reoviridae family. We plan to identify key steps in the VF formation and delineate their phase behavior with respect to stages of assembly. We will use combination of in vitro biochemical and biophysical approaches together with molecular biology and cell imaging techniques that allow to probe concentration,
composition, fluidity and structure of VFs. Such approach will answer questions about how VF are formed within cellular context, how and at what stage viral RNA gets recruited and replicated and whether virion
assembly and release are associated with further phase transitions. By comparing our results with those obtained in collaborating labs for related rotaviruses we will be in position to generalize and identify key common steps suitable for life cycle disruption. The goal is to establish molecular mechanism underpinning formation of reoviral replication factories in infected cells as a potential therapeutic target.
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Guanine crystals as nitrogen storage compartments in Chromera velia
Grant agency: GACR
Identification number of grant: 21-26115S
Head of the project: Ansgar Gruber (Biologické centrum AV ČR, v.v.i.)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Photosynthetic eukaryotes depend on external supply of nitrogen, and nitrogen availability is often limiting their growth rate. The cytosol of the alga Chromera velia, the closest known photosynthetic relative of apicomplexan parasites, contains a high abundance of crystalline inclusions, which we have shown to consist of the nitrogen rich compound guanine. Upon nitrogen starvation, the crystals decrease in size and numbers. When nitrogen is added to nitrogen-starved cells, crystals are re-formed. The guanine crystals might be storage compartments, which allow the accumulation of nitrogen beyond the immediate demand. This would mean that the purine catabolism is crucial for the mobilisation of stored nitrogen. By comparison to a photosynthetic alga that does not contain guanine crystals (the model diatom Phaeodactylum tricornutum), we will find out which enzymes, enzyme expression patterns, and metabolite transporters are needed to manage nitrogen storage in guanine crystals. Furthermore, we will determine how the stored nitrogen is passed on to daughter cells during mitosis. The aims of the project are, to (i) clarify the role of guanine crystals for growth and metabolism in Chromera velia, (ii) identify and characterize enzymes and transporters involved in guanine metabolism, (iii) identify proteins that enable the formation and maintenance of guanine crystals.
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Automatic evaluation of Raman spectral maps
Grant agency: TACR
Identification number of grant: Gama2 - 202108
Head of the project: Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Raman microscopy offers practical use in biology, medicine, and pharmacy, but also in biotechnology in the selection of suitable microorganisms, monitoring of production processes, or product quality control. This potential is far from being used in all its breadth and possibilities. Although the availability of instrumentation suitable for the biotechnology industry is increasing rapidly, software tools suitable for practical applications are still lacking. Raman microscopy is a combination of confocal laser scanning microscopy and vibrational spectroscopy, which together allow for non-destructive qualitative and quantitative analysis of material composition in microscopic resolution. In the case of biological material, it is mainly an analysis of the chemical composition of cells or tissues, where the most desirable output is the so-called Raman chemical maps describing the spatial distribution and concentration of individual chemical components in the studied objects. Although there are a number of measurement analysis programs for scientific purposes, there is a lack of software on the market to automatically process larger sets of similar data to replace manual operations with an algorithmic procedure, eliminate human factor
dependence, provide statistically relevant information about larger object sets, and thus speeded up and simplified data analysis. Ideally, the quantitative analysis should be available during the measurement,
preferably in real-time. Another problematic area is the interpretation of the measured spectra, which in the case of biological samples is not trivial without prior erudition and experience. This should ensure the
connection of the processing to the newly built databases of spectra of biological objects, especially single-celled organisms, which would be a functionality that is still lacking in this area. We build the database
from the spectra of chemical components measured directly on biological material, with validation using chemically pure standards. We design this database as online open-source (ramanbase.org).
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Růst a dělení ve stabilních izotopech - více než metabolické značení
Grant agency: GACR
Identification number of grant: 17-06264S
Head of the project: RNDr. Kateřina Bišová, Ph.D. (Mikrobiologický ústav AV ČR, v.v.i.)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Stabilní izotopy, neradioaktivní varianty prvků se stejným počtem protonů, ale různým počtem neutronů, jsou široce používány pro metabolické značení při studiu metabolickým toků a pro kvantitativní proteomiku. Deuterium, těžký stabilní izotop vodíku, má silné izotopové účinky a ve vysokých koncentracích způsobuje závažné změny buněčné fyziologie. Bezpečná hranice pro jeho zabudování do buněk rostlin a živočichů je 20 %. Přesto jsou některé zelené řasy schopné inkorporovat až 100 % deuteria a stále růst a dělit se. Není zřejmé, jaké mechanismy umožňují buňkám tolerovat vysoké úrovně deuterace. Navrhujeme porovnat dvě zelené řasy s různou reakcí na vysokou hladinu deuteria. Jedna z nich je schopná růstu a dělení i na 99 % deuteria, druhá zastaví růst a dělení jakmile poměr D2O/H2O přesáhne 0.70. Dva hlavní cíle návrhu jsou: 1) porovnat Ramanovou mikroskopií in situ dynamiku inkorporace deuteria u obou řas, 2) identifikovat předpokládaný/é regulátor/y umožňujících život při vysokých koncentracích deuteria.
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Interplay between chemical and plasmon-induced processes in plasmonic metal nanoparticles-molecules hybrid systems
Grant agency: GACR
Identification number of grant: 17-05007S
Head of the project: RNDr. Ivana Šloufová, PhD. (Přírodovědecká Fakulta UK)
Vice-head of the project:
Prof. RNDr. Marek Procházka, Dr.,
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
The main goal of the project is elucidation of the mechanisms of the chemical and of the the plasmon-induced processes in plasmonic metal nanoparticles/molecules hybrid systems, and of their mutual interplay in complex processes, such as plasmon-mediated surface reactions and chemically induced changes in plasmon-enhanced optical responses. This effort is targeted on obtaining tools for purposeful controlling of these processes in the selected plasmonic metal NPs molecules hybrid systems. The particular goals are: (i) revealing a possible plasmon-mediation of a particular surface reaction by a newly developer SERS (surface-enhanced Raman scattering) based strategy, (ii) development of the SERS spectral probes and/or the chemical sensors, (iii) generation and identification of new desired surface species, (iv) increasing the efficiency and/or reproducibility of plasmon-enhanced optical response sof the selected plasmonic metal nanoparticles/molecules hybrid systems.
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Nanokompozitní systémy plasmonických/magnetických nanočástic – grafenu – aromatických molekul pro zesílené Ramanské procesy
Grant agency: GACR
Identification number of grant: 15-01953S
Head of the project: RNDr. Ing. Martin Kalbáč, Ph.D. (Ústav fyzikální chemie J. Heyrovského AV ČR, v.v.i.)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Cílem projektu je návrh, příprava a studium nových nanokompozitních systémů na bázi grafenu, plasmonických (a/nebo magnetických) nanočástic a aromatických molekul, ve kterých je očekávana součinnost mechanismů přenosu náboje (CT) v grafenu a elektromagnetického (EM) v povrchově zesíleném Ramanském rozptylu (SERS). Ramanské rezonance budou řízeny energií rezonance povrchových plasmonů nanočástic, excitační energií a posunem Fermiho meze v grafenu. Magnetickým polem zesílený Ramanský rozptyl bude testován pro paramagnetické molekuly v systémech s nanomagnety. Aplikací vnějšího magnetického pole budou studovány vzájemné interakce SERS-aktivních komponent prostřednictvím modulace magneto-fononových rezonancí v grafenu a paramagnetických molekulách. Hlavním výstupem navrženého výzkumu jsou nové nanomateriály se synergií několika mechanismů SERS.
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Studium polymorfismu kvadruplexů nukleových kyselin
Grant agency: GAUK
Identification number of grant: 388615
Head of the project: Mgr. Kateřina Mudroňová
Vice-head of the project:
RNDr. Jakub Klener, Ph.D.,
Doc. RNDr. Peter Mojzeš, CSc.,
Václav Římal ()
Grant annotation
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Raman microspectroscopy of biological objects
Grant agency: GAUK
Identification number of grant: 82214
Head of the project: Mgr. Šárka Moudříková
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
The project is focused on assessment of chemical composition of cells
and cellular organelles in vivo using confocal Raman microspectroscopy.
The chemical composition with a spatial resolution of a few μm3 will be
obtained using multivariate statistical analysis of the measured Raman
spectra. Firstly, we will focus on solution of specific experimental and
technical problems of confocal Raman microspectroscopy of living cells,
which have so far been solved only partially. Specifically, we want to
address problems of keeping the cells in good condition during the
measurement, spatially fixing nonadherent cells, increasing signal to
noise ratio and increasing the effectiveness of measurement of large
statistical sets of biological objects. Next, we will focus on
simplifying the interpretation of the spectra and improving its
reliability. The acquired knowledge will be used to assess chemical
composition of organelles (e.g. vacuoles, liposomes) of living cells
cultivated under different conditions – for instance, we are interested
in the influence of chemical composition of the cultivation medium,
phase of the cell cycle, phase of the culture growth and various stress
conditions. The measurements will be performed on a model organism,
yeast Saccharomyces cerevisiae, pathogenic yeast Candida albicans and
other suitable cells and tissues.
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Engineering of surface-modified optical processes in molecules and semiconductor quantum dots by plasmon resonances in metal nanoparticle assemblies
Grant agency: GACR
Identification number of grant: P208/10/0941
Head of the project: Prof. RNDr. Blanka Vlčková, CSc. (Přírodovědecká Fakulta UK)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
The main goal of the project is development of tools for engineering of
surface-modified optical processes (namely luminiscence, resonance Raman
scattering, photochemistry and energy transfer) in molecules, molecular
ions and semiconductor quantum dots (SQDs) localized in plasmonic metal
nanoparticle (NP) assemblies towards the achievement of (i) enhancement
or (ii) quenching of the process as the predominant effect. Towards this
goal, parameters affecting the efficiency of the radiative as well as
non-radiative processes in molecules and SQDs located within, or in a
close proximity to the plasmonic metal NPs assemblies will be
systematically explored. A particular attention will be given to
investigation of the effects of (i) the overlap of the surface plasmon
resonance of the NPs assembly with the absorption and/or emision of the
selected luminophore (chromophore or donor and/or acceptor), and (ii)
the presence (or absence) of hot spots (strong-nanoscale localized
optical fields) within the plasmonic metal NP assembly.
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Development of device for non-invasive skin diagnostic
Grant agency: MPO
Identification number of grant: FR-TI2/246
Head of the project: RNDr. Vladimír Velebný, CSc. (CPN spol. s r.o.)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Currently, there is growing interest of physicians and scientists in
non-invasive diagnostic methods for investigation of the morphology,
physiology and chemical composition of skin and other tissues. The
present project deals with design of device that would combine optical
coherence tomography (OCT) with Raman microscopy (RM) for in vitro
non-invasive diagnosis of the skin to the depths necessary to monitor
formation of tumors in the course of cell division within the basal
layer of the skin. The objective of the project is to integrate both
techniques into a compact device with practical probe that could be used
in medical practice. The device would enable determination of the
chemical composition of the selected tissue by means of RS directly in
the points located by OCT.
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Noncanonical structures of nucleic acids and their interaction with cationic porphyrins
Grant agency: GAUK
Identification number of grant: 122208
Head of the project: Mgr. Jan Palacký
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
Cationic porphyrins can stabilize some non-canonical structures of
nucleic acids, e.g. guanine
quadruplexes, four-stranded structures rich in guanine identified in
originally single-stranded
regions of telomeric DNA. Development of novel cationic porphyrins
stabilizing guanine
quadruplexes more efficiently requires a detailed understanding of the
quadruplex structure
and of the stabilization mechanisms. Guanine quadruplexes are widely
studied mainly
because of their potential anti-cancer activity. Proposed grant project
will deal with formation,
structure and stability of various guanine quadruplexes as well as other
non-canonical
structures having potential biological or therapeutic significance, and
the role of the selected
cationic porphyrins and metalloporphyrins in the process. Methods of
optical spectroscopy
(UV-vis, CD, Raman), gel electrophoresis and scanning differential
microcalorimetry will
be applied. The aim of the research is to clarify role of the porphyrins
in the quadruplex
formation and stabilization.
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Chemické procesy podporované účinky laserového záření v systémech s plazmonickými nanočásticemi
Grant agency: GACR
Identification number of grant: 203/07/0717
Head of the project: Prof. RNDr. Blanka Vlčková, CSc. (Přírodovědecká Fakulta UK)
Vice-head of the project:
Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
None
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Biologicky a terapeuticky významné komplexy kationických porfyrinů a nukleových kyselin
Grant agency: GAUK
Identification number of grant: 224/2006/B-FYZ/MFF
Head of the project: Doc. RNDr. Peter Mojzeš, CSc.
Grant annotation
None