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Metabolite production by some strains of industrial yeasts in various phases of cell growth
Jankeje, Kristína ; Kubešová,, Jitka (referee) ; Kočí, Radka (advisor)
Presented bachelor thesis is focused on industrial application of chosen yeast strains. Principal interest of work is to study production of primary and secondary metabolites during individual growth phases. Optimal growth conditions as well as influence of exogenous stress factors (mainly oxidative and/or salt stress) on cell growth and yeast metabolism are discussed. In experimental part growth curve of industrial strain Phaffia rhodozyma was determined. Biomass increase (maximum in 90th hour 5,441 g/l), astaxanthin production (secondary metabolite) and/or ergosterol biosynthesis (primary metabolite) were observed. The best ration of astaxanthin to total carotenoids was 50 %. Next studied metabolite was ergosterol, its total amount in dry biomass was 0.11 %. In conclusion astaxanthin amounts produced in optimal growth conditions were compared with yields obtained under stress cultivations. Results of stress experiments illustrate positive influence of stress factors on cell growth as well as on astaxanthin biosynthesis. Low concentration of salt (2% NaCl) added in inoculum with 5 mM hydrogen peroxide in production medium would be the best combination in industrial applications.
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Comparison of sequence variations in genes of biotransfromation enzymes in some carcinoma
Turková, Lucie ; Tavandzis, Spiros (referee) ; Bóday, Arpád (advisor)
Xenobiotic biotransformation process and its capacity is crucial for xenobiotic chemicals elimination that may cause damage toward cell structures. The effectiveness of the enzymes included in this process depends on the gene variants that encodes them. The aim of this work was to compare certain polymorphisms of selected genes between cases and control groups. Studied polymorphisms were null genotypes of the glutathione S-transferase gene M1 and T1 and the insertion of TA dinucleotide in the promotor region of UDP-glucuronosyl transferase 1A1. The number of cases group was six included patients with colorectal, lung, prostate, breast, pancreatic and head and neck cancer. Total number of analysed individuals was 1 118 for cancer cases and 470 for healthy controls. The control group was divided into two groups, the first one was called general and the second one was called special included healthy individuals with no cancer history in their closest family members. Gilbert syndrome (GS) is caused by homozygous insertion of the TA dinucleotide in the TATA box of the gene UGT1A1 and it causes elevated bilirubin levels. Bilirubin is a potent antioxidant in human body, so the aim was to attest its protective effect toward cancer. We expected lower frequency of GS as a protective factor in the cases groups compared with controls. This hypothesis was confirmed in the breast cancer group (GS frequency 10,0 %) and pancreatic cancer group (GS frequency 11,1 %). In the general and special control groups the frequency of GS was 16,0 % and 15,4 % respectively. Although the other case groups show lower frequency of GS, the results weren´t statistically significant. Null GSTM1 genotype was observed with 50,4 % frequency in the general control groups and with 55,3 % frequency in the special control group. Neither the one of the cases groups hasn´t showed significantly lower percentage of null genotype. Despite expectation we observed statistically significant lower frequency of null genotype in the group of lung and pancreatic cancer group (37,4 % and 39,3 % respectively). According to this study, we can say that the lack of glutathione S-transferase M1 activity is not a risk factor for cancer development. Null genotype of GSTT1 wasn´t identified in both control groups at all. In case groups of breast and prostate cancer, there was only one individual carrying the null GSTT1 genotype. Statistically significant higher frequency of this polymorphism was observed in patients with colorectal cancer (9,7 %), lung cancer (17,2 %), pancreatic cancer (3,0 %) and head and neck cancer (15,9 %). In these groups the lack of glutathion S-transferase T1 activity might be considered as risk factor for cancer development. Nevertheless, for further verification it needs to take more investigation in this field, especially enlarge the number of patient in the case groups of head and neck, lung and pancreatic cancer.
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Evaluation of antibiotic-induced mitochondrial superoxide production in adherent cells
Ingrová, Kateřina ; Chmelíková, Larisa (referee) ; Zumberg, Inna (advisor)
The theoretical part of this bachelor´s thesis contains a description of the effect of reactive oxygen species on oxidative stress by mitochondria and the consequences of antibiotics use in cell line culturing. The cell line studied in this bachelor´s thesis is the mesenchymal stem cells (MSCs). The practical part describes the procedure of the experiment including cell culturing, passaging and cell labeling. The proposed experiment was repeated with sufficient number of repetitions. Finally, confocal microscopy images were processed in the MATLAB programming environment.
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Evaluation of glutathione content in plants as a marker of heavy metals environmental contamination
Borková, Marie ; Stoupalová, Michaela (referee) ; Opatřilová,, Radka (advisor)
Dependence of glutathione concentration on the amount of thallium in the plant was studied. Observed plant was maize (Zea mays) which was divided to two parts – root and overground. Two culture procedures were elaborated where seeds and young seedlings were cultivated in a solution of thallium of concentration 0, 1, 3, 5, 8, a 10 µmol/l. Extraction agents used during extraction were phosphate buffer and solution of ascorbic acid. Determination of glutathione was realized by capillary electrophoresis (CE) and high performance liquid chromatography (HPLC). Diode array detector (DAD) was used in both methods. Quantification of the thallium amount in the plant was done by method of inductively coupled plasma-atomic emission spectrometry (ICP-AES).
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The effect of air pollution on oxidative stress markers in newborns
Ambrož, Antonín ; Rössner, Pavel (advisor) ; Rubeš, Jiří (referee) ; Gábelová, Alena (referee)
In everyday life, humans are exposed to toxic substances of anthropogenic origin. These substances can also be found in the ambient air and their impact poses a long-term risk for human health. Respirable particulate matter (PM) of aerodynamic diameter < 2.5 µm (PM2.5) is intensively studied, along with carcinogenic polycyclic aromatic hydrocarbons (PAHs), bound to it, such as benzo[a]pyrene (B[a]P), a reference carcinogenic PAH. Owing to small size, PM2.5 can penetrate the human body primarily via the airways and represent an increased health risk compared to larger particles. The negative health impacts of anthropogenic PM2.5, generated e.g. by fossil fuel combustion, are linked with its small size, relatively large surface, as well as with PAHs and other substances adsorbed on PM surface. PAHs, generated by an incomplete combustion of organic matter, can enter organism either via ingestion of contaminated food, water or via inhalation of polluted air. PAHs affect organisms via genotoxic, mutagenic, carcinogenic, embryotoxic and other adverse effects. One of the common denominators of these effects is oxidative stress, which is also considered to be the main mechanism of action caused by PM in the human organism. Oxidative damage induced by reactive oxygen species (ROS) may affect any cellular...
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Redox signaling to chromatin
Plšková, Zuzana
Chromatin is a highly dynamic structure, which is constantly subjected to regulation in response to environmental conditions. This response is mediated by chromatin modifiers, such as histone acetyltransferases, which deposit histone post-translational modifications, resulting in changes in gene expression. One of such modifiers in plants is GENERAL CONTROL NON-REPRESSIBLE 5 (GCN5). Despite its importance in plant growth and development, it remains poorly understood how GCN5 is regulated. Emergine evidence points towards redox regulation of chromatin remodeling that can be executed via redox modifications of chromatin modifiers. To investigate possible redox regulation of GCN5, we used redox insensitive lines, carrying GCN5 with mutated cysteine to serine. Even though gcn5 mutants displayed enhanced susceptibility to paraquat-induced oxidative stress, the mutated lines phenocopied the wild type. We further probed the interactome of GCN5 to identify putative functional partners, whose association with GCN5 could be altered under oxidative stress conditions, or affected by its redox status. Mutating of a single cysteine residue in GCN5 did not result in significant changes of its interactome, suggesting that additional single and higher order mutants need to be explored.
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Pathophysiological and genetic factors affecting serum uric acid level.
Hasíková, Lenka ; Závada, Jakub (advisor) ; Hrnčíř, Zbyněk (referee) ; Horák, Pavel (referee)
Introduction: Serum uric acid level (SUA) depends on the balance between its production and excretion. SUA is associated with several transmembrane proteins responsible for reabsorption (mainly URAT1 and GLUT9) and secretion (ABCG2) on the apical and basolateral membranes of the proximal tubules in the kidney, and in the case of ABCG2, it also correlates with its significant excretion through the gastrointestinal tract. Gout is a metabolic disease caused by the deposition of urate crystals in the joints and tissues. Chronic hyperuricemia is a primary risk factor for the development of gout; however, gout patients usually have a lower SUA during an acute gout attack than in the intercritical periods. The exact mechanism of this phenomenon is unknown. It has been speculated that the systemic inflammatory response can explain this discrepancy. The aim of the study is to determine whether treatment with specific inhibitors of the proinflammatory cytokine TNF (TNFi) affects SUA in patients with systemic rheumatic disease (SRD), and whether changes in SUA correlate with changes in selected proinflammatory cytokines or with the biomarker of oxidative stress, allantoin. Another aim is to determine the frequency and effect of allelic variants in the ABCG2 urate transporter gene in patients with primary...
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The effect of yttrium and samarium oxide nanoparticles on plant development
Brandová, Zuzana ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
This thesis is based on hydroponic experiment conducted on Hordeum vulgare with nanoparticles of rare earth elements in concentration 2·10-4 mol/L and REEs chlorides in concentration 3·10-4 mol/L. The comparison of the the effect on their acumulation of another nanoparticles in the sloution and normal medium is included as well. In this case the hydroxyapatite NPs were chosen in the same concentration as yttrium and samarium NPs. The role of type and form of the elements on their acumulation and impact is also studied. Negative effect of REEs was proven by enzymatic analysis that detects reducting enzymes and determination of plant pigment levels by high performance liquid chromatography. Because both types of substances can reduce reactive oxygen radicals. Acumulation of REEs was determined by ICP spektrometry. Key words: nanoparicles, reare earth elements, reductive enzymes, plant pigments, acumulation, oxidative stress
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Heme sensor proteins as potential biomarkers of cellular and oxidative stress processes induced by ionizing radiation
Vávra, Jakub ; Martínková, Markéta (advisor) ; Souček, Pavel (referee) ; Tichý, Aleš (referee)
[IN CZECH] Ionizing radiation is a potential inducer of the oxidative stress processes in cells. As a result, reactive radicals are formed in the intracellular space modifying the essential biomolecules. Ionizing radiation has either direct (radiation sickness) or indirect (malignant processes) effect on the organism. Therefore, a fast determination of the dose is required when suspected irradiation of the organism occurs. However, a method routinely applicable, fast enough and at the same time suitable for dose estimation based on biomarkers has not been developed so far. The aim of this thesis is to describe new properties of the selected heme sensor proteins and discuss their potential importance for the cellular adaptation to oxidative stress conditions. Specifically, the thesis is focused on two eukaryotic proteins, heme regulated inhibitor (HRI) and transcription factor p53. The study of functional regulation as well as the conformational changes of these proteins induced by heme is greatly emphasized. Besides, the optimization of the key experimental methods was conducted. Specifically, Phos-tag electrophoresis was applied for the kinetics study of HRI wild type and its Gly202Ser mutant form, which is a characteristics of lung cancer development. Unsurprisingly, for both HRI forms studied,...
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Role of oxidative stress in male infertility.
Dolečková, Barbora ; Tlapáková, Tereza (advisor) ; Šanovec, Ondřej (referee)
Oxidative stress is a phenomenon caused by an excess of reactive oxygen species (ROS), or by insufficient activity of antioxidants, that reduces these ROS levels and thereby protect the organism from oxidative damage. ROS have two types of origin: endogenous, which includes leukocytes and immature sperm, and exogenous, which includes factors such as air pollution caused by heavy metals, smoking tobacco products, obesity and others. Low levels of ROS have a positive effect on the physiological functions of the organism, including the process of spermatogenesis, where ROS participates in the course of hyperactivation and capacitation. However, increased levels of ROS trigger a number of cellular pathologies, whether the loss of fluidity of biological membranes due to lipid peroxidation, deformation of enzymatic proteins or DNA fragmentation, which negatively affects individuals' infertility. Due to the significant positive correlation of ROS scavenging by antioxidants with improving sperm parameters of an infertile individual, antioxidant therapy has recently begun to be used as a possible successful component of male idiopathic infertility treatment.
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