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Mineral nutrient transporters and root system efficiency
Schmidová, Dominika ; Tylová, Edita (advisor) ; Kobercová, Eliška (referee)
Plants are sessile organisms whose survival depends largely on the ability to ensure sufficient water and mineral nutrient uptake by the root system. To this end, plants have evolved specialised transport systems that ensure selective uptake of essential elements and also allow plants to adapt to varying soil nutrient concentrations. In terms of transport kinetics, mineral nutrient transporters are of two types - high-affinity and low-affinity. Depending on the nutrient concentration in the soil, plants can engage each type to maximise nutrient uptake. In addition to the efficient setup of transport processes at the membranes, there are other mechanisms in the plant to maximize the uptake of soil resources. These are mainly changes in the architecture of the root system. In addition to the systemic growth response, plants regulate root growth at the local level in response to uneven nutrient distribution in the soil. This response is limited to a specific part of the root system, which adapts to use that area as efficiently as possible. In addition to their transport function, mineral nutrient transporters also play a sensory role in the regulation of localised root growth. The aim of this bachelor thesis is to describe the uptake mechanism of the important essential macronutrients, nitrogen,...
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Application of Atomic Absorption Spectrometry for Determination of Selected Elements from Potential Ecological Burden Area
Juránková, Lada ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This work is focused on the determination of selected (chemical) elements (Fe, Mn, Zn, Cr, Na, K, Mg a Ca) in a potential ecological burden area using flame atomic absorption spectrometry as a detection technique. A potential ecological burden is represented by tires which are used as a construction material or as an environment surrounding for growing decorative and consumable plants. Analytes were determined in plant origin samples. Firstly, the samples were dried in a laboratory electric dryer. The weighted amount of a dried sample (approximately 0.2 g) was digested inside a microwave decomposition device with an addition of nitric acid and hydrogen peroxide. An optimization of experimental parameters was done for each of the elements before sample measuring. A burner height was optimized and 8 mm height was chosen as a optimum for most elements. Under the optimum condition basic characteristics were measured for each element separately. These characteristics included limits of detection that were: 0.05; 0.01; 0.08; 0.21; 0.02; 0.01; 0.01; 0.01 mg L-1 for the following elements: Fe, Mn, Zn, Cr, K, Ca, Mg and Na, respectively. The limits of quantification, sensitivity and repeatability were determined for each element as well. A significant attention was paid to the content of zinc in the studied...
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Function of the AtKUP5 transporter in Arabidopsis thaliana
Štočková, Hana ; Tylová, Edita (advisor) ; Hála, Michal (referee)
Potassium is one of the essential elements necessary for plant growth. It is involved in many plant processes, such as osmoregulation, enzymes activaton, etc. These functions are very often closely related to its transport in the cell and the whole plant. Although potassium is abundant in earth's crust, the mount of plant-available form is often insufficient. Potassium deficiency manifests itself on many levels and also contributes to the reduction of yield and quality of agricultural crops. There are many of potassium-transporting proteins in the plant. One of the important families of potassium transporters is the KT/HAK/KUP family. This family includes, among others, the high-affinity transporter HAK5, which is key for the uptake of potassium from the environment with low-potassium availability. One of the not very characterized transporters from the KT/HAK/KUP family is the KUP5 transporter, which I deal with in my diploma thesis. The aim of this work is to analyze the phenotypic manifestations of kup5 T-DNA insertion mutants and to characterize the functions of the transporter KUP5 in Arabidopsis thaliana plants. I analyzed the growth of kup5 insertion mutants in various environmental conditions and performed plant transformation to determine the localization of the KUP5 transporter in the...
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Transporters KT/HAK/KUP - role in plant development and response to environmental conditions
Doležalová, Barbora ; Tylová, Edita (advisor) ; Hála, Michal (referee)
Potassium is an essential element, which is important in many plant processes. It functions as a major osmotic and is involved in the regulation of turgor during cell growth or stomatal movements. It is also important for maintaining membrane potencial. In plants, potassium transporters from the KT/HAK/KUP family are involved in the transport of K+ . Some of them are important in the uptake of K+ from the enviroment (HAK5, KUP7), others in regulation of cell turgor (KUP2, KUP6, KUP8). In Arabidopsis thaliana, less characterized KT/HAK/KUP transporters include KUP5 and KUP9, which I studied in this diploma thesis. In this diploma thesis, I analyzed the growth phenotype of kup5 mutant plants. The results show that kup5 mutant plants are not more sensitive to K+ deficiency than wild-type plants, therefore KUP5 is probably not involved in the K+ uptake from the enviroment. Kup5 mutant plants were larger than wild-type plants, had larger root and hypocotyl cells as well as longer root meristematic zone. This growth phenotype suggests that KUP5 is involved in the regulation of cell growth, probably through turgor regulation. Using the pKUP5::KUP5-GFP construct, the KUP5 protein was localized in the ER, but this localization needs further verification. Using the pKUP5:GUS construct, KUP5 expression was...
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Determination of sodium and potassium in honey samples by atomic absorption spectrometry
Venclová, Veronika ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This bachelor thesis was focused on the determination of sodium and potassium in honey samples by atomic absorption spectrometry with a flame atomization technique. An acetylene-air flame was used. Prior to the analysis of the honey samples, the optimal working parameters of the used method were found. The optimized parameters were: the height of the beam above the burner, the flow rate of acetylene, and the burner's horizontal position. Under the optimal conditions, the basic characteristics of the determination of sodium and potassium were studied. Sodium and potassium concentrations in the honey samples were determined under optimal conditions. A total number of 27 honey samples were analyzed. The sodium content ranged from 0.880 to 25.3 mg/kg. The potassium content was in the range of 223 - 2750 mg/kg. In the end, the measured concentrations of honey samples originating from the Czech Republic were compared with the foreign studies. Keywords Potassium, sodium, honey, atomic absorption spectrometry, flame spectrometry
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Application of spectral and non-spectral analytical methods for monitoring the quality of ketchups
Havlíčková, Barbora ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
The aim of the master´s thesis was to verify the applicability of elemental analysis and molecular spectrometry for examining the authenticity of ketchup. For verify of share refractometric dry matter introduced into ketchup from tomatoes was used analysis of potassium and lycopene content. Ketchups with different tomato contents were prepared and subsequently models were created, which were used to verify the proportion of refractometric dry matter introduced into tomato ketchup in ketchups from the store. The results of the work showed that the amount of lycopene is a problematic marker for verifying the authenticity of ketchup, because during the production of ketchup, lycopene is degraded.In contrast, the amount of potassium in ketchup has been shown to be a good marker for monitoring the authenticity of ketchup. The model based on the potassium content of ketchup worked reliably, the deviations obtained from the quantity of tomatoes used for the production of ketchup indicated on the packaging were less than 10%. Higher deviations were achieved in ketchups with a minimum permitted tomato content of up to 20%. The concentration of potassium in ketchup with a lower content of used tomatoes can be significantly affected by the addition of other ingredients to the ketchup (onion, garlic, carrot, apple, etc.). In addition to the ketchup production technology used, the ripeness of tomatoes also has a significant effect on the model for verifying the authenticity of ketchup.
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Mechanisms of exodermal response to nutrient availability in the environment
Gargoš, Ondřej ; Tylová, Edita (advisor) ; Kummerová, Marie (referee)
in English The apoplastic barriers of the root (endodermis and exodermis) represent an important regulatory mechanism for the uptake of water and nutrients from the environment, ensuring its selectivity. In addition, both layers respond to stress factors by altering its rate and degree of cell wall modification, which affects the transport properties of the root and represents adaptive plants to high heterogeneity of the soil environment. Apoplastic barriers also respond to the availability of mineral nutrients. This issue has recently been intensively studied and a number of ambiguities persist. Interestingly, the deficiency of some mineral nutrients stimulates the differentiation of barriers, while the deficiency of other mineral nutrients delays the differentiation. In addition, different plant species react differently to the deficiency of the same element. Another interesting aspect is the fact that the reaction of the endodermis and exodermis is localized and takes place mainly in that part of the root system which is directly exposed to the stress factor. This phenomenon has been observed with cadmium toxicity, but more recently with local nutrient deficiencies (nitrogen and potassium) in Zea mays. This diploma thesis deals with the functional significance of localized enhancing or delaying...
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Simulation of processes in cellular membranes
Melcr, Josef ; Jungwirth, Pavel (advisor)
Simulation of processes in cellular membranes Abstract Many important processes in cells involve ions, e.g., fusion of synaptic vesi- cles with neuronal cell membranes is controlled by a divalent cation Ca2+ ; and the exchange of Na+ and K+ drives the the fast electrical signal transmis- sion in neurons. We have investigated model phospholipid membranes and their interactions with these biologically relevant ions. Using state-of-the-art molecular dynamics simulations, we accurately quantified their respective affinites towards neutral and negatively charged phospholipid bilayers. In order to achieve that, we developed a new model of phospholipids termed ECC-lipids, which accounts for the electronic polarization via the electronic continuum correction implemented as charge rescaling. Our simulations with this new force field reach for the first time a quantitative agreement with the experimental lipid electrometer concept for POPC as well as for POPS with all the studied cations. We have also examined the effects of transmembrane voltage on phospholipid bilayers. The electric field induced by the voltage exists exclusively in the hydrophobic region of the membrane, where it has an almost constant strength. This field affects the structure of nearby water molecules highlighting its importance in electroporation. 1
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Determination of selected elements in potato tubers by atomic absorption spectrometry
Fořtová, Lucie ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
The main aim of this bachelor thesis was a determination of the elements K, Mg, Ca, Na, Zn and Fe in the potato tubers and in their boiled solution using the method of flame atomic absorption spectrometry. The chosen samples were late consumer potato tubers of Granada cultivar (boiling type B). It was necessary to optimize working conditions before the sample analysis. The optimal flow rate of acetylene ranged from 2.0 to 2.5 l/min using the flame acetylene-air. The flame acetylene-nitrous oxide was used only for calcium with flow rate 6.0 l/min. The optimal height of a beam above the burner edge was measured in interval 5 to 7 pieces of defined scale mentioned in a manual for spectrometer GBC 933 AA. Using the optimal conditions, the basic characteristics for individual methods of determination were characterized (LOD, LOQ, LDR, sensitivity, repeatability). Limits of quantification were following: 78, 31, 7.0, 8.0, 190 and 71 μg/l for K, Na, Mg, Ca, Fe and Zn, respectively. The optimal conditions were used for the determination of the selected elements in samples. The solutions were prepared from diversely processed potato tubers (whole, whole without skin, chopped without skin, skin) by boiling into deionized water. After the samples had cooled down, the concentrated nitric acid was added...
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Function of the AtKUP5 transporter in Arabidopsis thaliana
Štočková, Hana ; Tylová, Edita (advisor) ; Hála, Michal (referee)
Potassium is one of the essential elements necessary for plant growth. It is involved in many plant processes, such as osmoregulation, enzymes activaton, etc. These functions are very often closely related to its transport in the cell and the whole plant. Although potassium is abundant in earth's crust, the mount of plant-available form is often insufficient. Potassium deficiency manifests itself on many levels and also contributes to the reduction of yield and quality of agricultural crops. There are many of potassium-transporting proteins in the plant. One of the important families of potassium transporters is the KT/HAK/KUP family. This family includes, among others, the high-affinity transporter HAK5, which is key for the uptake of potassium from the environment with low-potassium availability. One of the not very characterized transporters from the KT/HAK/KUP family is the KUP5 transporter, which I deal with in my diploma thesis. The aim of this work is to analyze the phenotypic manifestations of kup5 T-DNA insertion mutants and to characterize the functions of the transporter KUP5 in Arabidopsis thaliana plants. I analyzed the growth of kup5 insertion mutants in various environmental conditions and performed plant transformation to determine the localization of the KUP5 transporter in the...
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