Science and Technology - Bachelor's theses. Kuni 2024

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    Acylation of N-Boc-N’-COCF3 protected hydrazine
    (Tartu Ülikool, 2024) Kurbanova, Karina; Mastitski,Anton, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Within the scope of the present thesis acylation of N-Boc-N’-COCF3 protected hydrazine was investigated. Acetic anhydride, benzoyl and butanoyl chlorides, activated esters and benzyl chloroformate were tested as acylating agents. The implementation of highly reactive acyl chlorides led to very good yields of hydrazines monoacylated at the Boc-protected nitrogen. Application of an excess of acyl chlorides promoted the formation of diacylated Boc-protected hydrazines and an unexpected loss of the trifluoroacetic group. Acylation by activated esters or benzyl chloroformate resulted solely in monoacylated products isolated in fair to poor yields. Reactions utilizing acetic anhydride gave no product irrespective of reaction conditions.
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    Development of Control Electronics and Program for Robotont's Height Adjustment Mechanism
    (Tartu Ülikool, 2024) Volynets, Veronika-Marina; Raudmäe, Renno, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    In today's dynamic landscape, robotics, and automation have become indispensable across various sectors, from enhancing efficiency in manufacturing processes to improving patient care in healthcare, the impact of these technologies is profound. Robotics and automation have the potential to revolutionise various sectors by boosting productivity, ensuring precision, and enhancing safety. However, the full potential of these technologies remains underutilised due to significant barriers, particularly the shortage of a skilled workforce capable of operating and the lack of tools that can be used in robotic engineering and experimentation. To address these challenges, the control electronics for the scissor-lift mechanism made by fellow student Kertrud Geddily Küüt was built and programmed as a multifaceted educational and research tool with a practical use in various fields of work. Enabled by our programming, we equipped it with user-friendly controls that allow for precise platform control, facilitating immersive learning experiences and hands-on experimentation. As a core component of the Robotont open-source initiative, it serves as a catalyst for practical learning in robotics and automation. In summary, our work on the electronic controls and programming of existing scissor lift mechanism fills a crucial gap in robotics education, empowering students and professionals with the skills necessary to thrive in today's technology-driven world. By providing a user-friendly platform for practical experimentation, it not only enhances learning outcomes but also fosters collaboration and innovation within the robotics community.
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    Image similarity usage in order to find similar items in E-commerce dataset
    (Tartu Ülikool, 2024) Dossymbekov, Adilet; Avots, Egils, juhendaja; Makarov, Aleksandr, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    This thesis looks into the e-commerce situation among small businesses and examines the possibility of the application of neural networks to business-to-consumer interactions. The goal of the study is to test the ability of NN to work with limited data and hardware. Pre-trained ResNet-50 model was used as a base, and fine-tuned with the 4 class dataset, consisting of 2906 images of clothes categorised into four classes. The experiments were conducted on a budget-friendly hardware setup. Both the dataset and hardware reflect the limited resources of the small and micro businesses The final model was evaluated, reaching an accuracy of 70-80%, These results suggest the possibility of NN usage in limited data and computational resource conditions and provide the base for further developments in implementing NN among small businesses.
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    Generative AI-based Style Recommendation Using Fashion Item Detection and Classification
    (Tartu Ülikool, 2024) Kalinin, Aleksandr; Anbarjafari, Gholamreza, juhendaja; Jafari, Akbar A., juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    This thesis describes the creation of a cutting-edge style recommendation system that uses generative AI and deep learning approaches to analyse fashion photos. The system is intended to process input images, such as selfies or studio-quality photos, and output a text file with extensive feedback on the individual’s style and suggestions for improvement. The system consists of two main components: the YOLOv8 convolutional neural network, which detects and crops clothing items, and the GPT-4.0 large language model, which generates informative style commentary and recommendations. YOLOv8 is briefly trained on a specific dataset to improve its performance in recognising 10 different types of clothes, while GPT-4.0, which is accessible via the OpenAI API, is charged with giving cohesive and short style suggestions. To evaluate the success of the suggested solution, real experimental trials were conducted at many events in Madrid and Tallinn. Three well-known AI models were used for comparison: OpenAI’s GPT-4.0 Vision, Google’s Gemini 1.5 Pro, and Anthropic’s Claude 3 - Opus. Participants judged the quality of each model’s fashion recommendations. The results showed that GPT-4.0 Vision and Gemini 1.5 Pro had comparable average ratings, indicating higher perceived quality than Claude 3 - Opus. This thesis demonstrates how cutting-edge computer vision and natural language processing technology may transform personalised fashion advising services, improving accuracy and relevance of style recommendations.
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    Flexible Screen Integration and Development of Neck Movement Mechanism for Social Humanoid Robot SemuBot
    (Tartu Ülikool, 2024) Kurenkov, Nikita; Kruusamäe, Karl, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Effective communication and interaction are pivotal for integrating humanoid robots into human-centric environments. Central to the functionality of a social humanoid robot is its ability to engage with humans through facial expressions and neck movement gestures. This thesis focuses on the critical task of designing and implementing solutions for the face of a humanoid robot and developing a corresponding neck mechanism to enhance the communicative abilities of humanoid robots. The research entails designing, experimenting, and integrating a work solution for a humanoid robot's face and neck mechanism of a social humanoid robot, SemuBot. The project uses computer-aided design modelling and 3D printing. The implementation involves utilising specialised hardware such as flexible screens, stepper motors for neck actuation, and microcontrollers for seamless integration and control. Additionally, the development process involves iterative design, testing, and integration of the flexible screen and neck mechanism. This work culminates in presenting a functional prototype, demonstrating the proposed facial and neck mechanism solutions' efficacy in enhancing the robot's social interaction capabilities and overall human-like appearance.
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    Non-precious metal electrocatalysts for oxygen reduction via ionothermal synthesis
    (Tartu Ülikool, 2024) Ibrahim, Faruq Olamilekan; Kisand, Kaarel, juhendaja; Tammeveski, Kaido, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    The increasing global energy demand necessitates the development of sustainable energy technologies. Anion-exchange membrane fuel cells (AEMFCs) present a promising alternative to proton-exchange membrane fuel cells (PEMFCs) due to their ability to utilize platinum group metal (PGM)-free catalysts, which significantly reduce costs and resource dependency. This thesis focuses on the synthesis, characterization, and performance evaluation of transition metal and nitrogen-doped carbon catalysts for AEMFCs. Utilizing cyclodextrine and magnesium nitrate, various PGM-free catalysts were developed, and the synthesis conditions were optimized. The catalysts were investigated with both physical and electrochemical characterization techniques. The catalysts' performance was assessed through rotating disk electrode (RDE) measurements and single-cell AEMFC tests. The optimized FeNC-CD3 catalyst exhibited a peak power density of 596 mW cm⁻², showcasing its potential as a viable alternative to conventional Pt-based catalysts. This work highlights the critical role of hierarchical porosity in enhancing oxygen reduction reaction (ORR) activity and paves the way for the development of cost-effective and efficient AEMFC technologies.
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    Design and Control of a Social Humanoid Robot - SemuBot’s Hand
    (Tartu Ülikool, 2024) Huseynov, Elchin; Aabloo, Alvo, juhendaja; Zinatullin, Leonid, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Children can find socialising difficult due to communication problems and a lack of comprehension of social cues[1], which can lead to isolation, marginalisation, and difficulties building social bonds. Social robots are an effective solution to this problem[2]. But, social robots need to be embodied as a humanoid for children to create a will to socialise with the robot. There are several versions of social humanoid robots. However, most are prohibitively expensive and difficult to repair because they’re closed-source. SemuBot is one of the projects that aims to solve these issues and help tackle children's socialisation issues. Semubot is a student-led, nonprofit organisation. This work pertains to the arm and the forearm parts for the SemuBot. Natural interactions between machines and humans require the robot to display body language, requiring robotic hands. However, the hand designs that are currently available either have expensive and/or noisy actuation systems. Some also have insufficient degrees of freedom, limiting the number of gestures they can make. In this work, we present an open-source, modular hand with 7 actuated degrees of freedom. The design incorporates a bio-inspired tendon-driven actuation mechanism, which uses cost-effective materials and off-the-shelf components to achieve common hand gestures.
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    Medi_Vizz: A tool for concurrent visualisation of medical data
    (Tartu Ülikool, 2024) Dyn’ko, Uscinnia; Haller, Toomas, juhendaja; Nurm, Miriam, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Doctors must analyse the extensive amount of medical data before diagnosing a patient and prescribing treatment. This is especially complicated for patients with multiple chronic conditions, who can be treated by different specialists. The advent of electronic health records granted doctors the opportunity to have all the available information at hand – on the computers at their workstations. However, the challenge of representing these data in an easy-to understand way remained. The Medi_Vizz application allows doctors to visualise individual patients' diagnoses and laboratory analysis data. Medi_Vizz has a user-friendly interface and creates comprehensible plots with medical data. Doctors can utilise these plots in clinical decision support, while scientists can examine disease progression in individual patients, making Medi_Vizz a valuable tool for both general healthcare and scientific research.
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    Thymic rejuvenation with GHS tesamorelin in a “dirty” mouse model
    (Tartu Ülikool, 2024) Ligere, Anita; Haljasorg, Uku; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Age-related thymic involution is one of the major reasons behind compromised adaptive immune responses in the elderly. It is characterized by the progressive reduction in thymic mass, accumulation of adipose tissue within the thymus, and disruption of unique thymic structure, which results in impaired T cell development and reduced naïve T cell output with age. Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) treatments have shown promise in restoring the functionality of the aged thymus albeit with unwanted side effects. While GH secretagogue (GHS) ghrelin has thymus-rejuvenating effects, the effects of a similar GHS called tesamorelin have not yet been studied. Since tesamorelin stimulates endogenous GH production similar to ghrelin and has fewer metabolic side effects than exogenous GH treatment, we hypothesize that it could have positive effects on thymus functioning and T cell development. In this study, the effects of tesamorelin on T cell populations in the thymus, as well as secondary lymphoid organs, were investigated using the “dirty” mouse model that better resembles the human immune system than conventional SPF mice. We report that while tesamorelin does not have thymus-rejuvenating effects in the 6.5- month-old “dirty” mice, it does promote the accumulation of antigen-experienced memory T cell subsets and decrease of naïve T cell subsets in the murine spleen. Although further research is required, we suggest this splenic accumulation is the reflection of the decreased levels of activated cytotoxic T cell markers in the peripheral blood of HIV patients treated with clinical grade tesamorelin.
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    Search for missing components in high VPD-induced stomatal closure pathway
    (Tartu Ülikool, 2024) Morozova, Daana; Merilo,Ebe, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Climate warming is associated with rising atmospheric Vapour Pressure Deficit (VPD), which affects plant physiology and production. Some proteins in the high VPD-induced stomatal closure pathway are known (e.g., protein kinase OST1), but there are still missing components. To address this knowledge gap, the study aimed to investigate Arabidopsis mutants defective in selected genes in order to reveal new elements that might be involved in VPD-induced stomata closure. Mutants were selected based on Wang et al. (2020) table of OST1 putative substrates and the expression levels of these genes in guard cells versus mesophyll cells. Experiments were conducted using a gas exchange measurement device to study plants’ stomatal conductance in response to high VPD and a plant stress hormone - abscisic acid (ABA). The study results showed no statistically significant differences in the steady-state stomata conductance and closure responses among mutants and wild-type, suggesting that these genes are not involved in VPD-induced stomata closure. Therefore, more studies are needed to reveal the missing components in the stomatal high VPD-induced closure pathway above OST1. Current results still add knowledge about stomatal behavior in future climatic conditions.
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    Automated Detection and Quantification of Stomata
    (Tartu Ülikool, 2024) Gorbachenko, Ivan; Hõrak, Hanna, juhendaja; Haamer, Rain Eric, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    This thesis presents an approach for the automated detection and quantification of stomata using machine learning techniques. The study focuses on employing the YOLOv8 model to analyse video data of leaf epidermal imprints, significantly improving the efficiency and accuracy of stomatal detection compared to traditional manual methods. The results highlight the model's ability to handle varying focal depths within video frames, ensuring consistent stomatal counts. Future research directions include expanding the dataset and incorporating advanced image analysis techniques to further enhance detection accuracy.
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    The role of SPEN3 in stomatal development and plant growth in Arabidopsis thaliana
    (Tartu Ülikool, 2024) Mammadzada, Nargiz; Hõrak, Hanna, juhendaja; Jalakas, Pirko, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Stomata are small openings on the surface of the leaves, which are crucial for plants’ gas exchange. Thisstudy focused on analyzing stomatal density and conductance in plants deficient in the SPEN3 gene. SPEN3, as an RNA-binding protein, assists in transcriptional regulation, posttranscriptional processing, and nuclear export of mRNA. By growing plants under controlled conditions, taking stomatal imprints and measuring stomatal conductance we were able to assess stomatal traits in wild-type and spen3 mutants. Those assessments showed a lower stomatal density on the bottom leaf side of the spen3 mutants compared to wild type plants, whereas no statistically significant differences in stomatal conductance or plant growth were observed. Further studies are needed to elucidate the role of SPEN3 in plant water use efficiency.
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    Real-Time Detection of Robot Failures by Monitoring Operator’s Brain Activity with EEG-based Brain-Computer Interface
    (Tartu Ülikool, 2024) Podliesnova, Veronika; Kuzovkin, Ilya, juhendaja; Kruusamäe, Karl, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    The rapidly growing field of Brain-Computer Interfaces (BCIs) provides an innovative method for human-robot interaction, enabling machines to be controlled directly via brain signals. This study investigates the use of BCI technology to monitor the operator’s brain activity in real-time and detect robot malfunctions through the identification of Error-Related Potentials (ErrPs). In this thesis, a real-time system was developed to monitor the brain activity of robot operators continuously using an OpenBCI consumer-grade EEG device. Machine learning algorithms were implemented to analyze brain activity, specifically targeting ErrPs, which indicate that the operator is noticing something unexpected. By recognizing these brain signals, our system can identify potential robot malfunctions based on the operator’s cognitive response and trigger an immediate halt to the operation. This system integrates several key components: signal processing techniques such as resampling, filtering, and normalization to prepare the EEG data for analysis; machine learning classifiers to identify ErrPs associated with robot malfunctions; a robotic simulation that generates realistic scenarios to elicit ErrPs in participants’ brain activity for safe system testing; and real-time brain signal acquisition allowing immediate detection of ErrPs and response to faults. All these components are packed into one coherent system that detects robot malfunctions and triggers intervention. The final system underwent live testing with 10 participants, demonstrating its capability to detect ErrPs associated with robot malfunctions effectively. These tests showed that the system achieves an average sensitivity of 0.53 while maintaining a specificity of 0.98, suggesting that the system rarely reacts without a valid reason while being able to correctly detect more than half of the events of interest. For some users, sensitivity reached as high as 0.7 or more. These findings demonstrate the potential of consumer-grade EEG devices for practical applications of BCI-based robot fault detection.
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    Antibodies targeting glucose transporter GLUT1 developed through the methods of Phage Display
    (Tartu Ülikool, 2024) Planken, Jaan Eerik; Teyra, Joan, juhendaja; Tenson, Tanel, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Cancer immunotherapy has emerged as a major treatment approach to combat malignant cells. Among the potential targets, the glucose transporter 1 (GLUT1) stands out due to its role in facilitating the increased glucose uptake characteristic of cancer cells. In this thesis, we use the methods of phage display technology to isolate GLUT1-specific antibodies from a diverse phage library constructed from a previously immunized chickens spleen cells. Through four rounds of panning against a GLUT1-overexpressing virus-like particle (VLP), with each round increasing in stringency, we were able to identify 27 unique antibody sequences. All obtained unique antibodies show great specificity towards the GLUT1 VLP, with signals averaging 11 times higher, on an ELISA based binding assay, in comparison to an off-target antigen control.
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    Post-Quantum Secure Cloud Computation Over Encrypted Data
    (Tartu Ülikool, 2024) Gulmammadov, Toghrul; Farzaliyev, Valeh, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    In recent years, cloud computing has gained significant popularity as businesses increasingly use it for data training purposes. However, this widespread adoption raises privacy concerns, particularly in light of regulations such as the GDPR. Additionally, there is an imminent need to prepare for the potential threats posed by quantum computers, which can easily break most current encryption methods. In response to these challenges, we have undertaken research on "Post-Quantum Secure Cloud Computation Over Encrypted Data" to address privacy issues in a manner resilient to quantum attacks. Our study provides a detailed proof of concept, using Zama’s "Encrypted Health Prediction" tutorial as an example, to demonstrate the feasibility and practicality of creating SaaS applications that are secure against quantum threats and capable of training encrypted data in the cloud.
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    Effect of L-DOPA on Sensory Function in vivo
    (Tartu Ülikool, 2024) Rusetskaya, Anna; Hickey, Miriam Ann, juhendaja; Faisal, Mahvish, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Levodopa (L-DOPA) is a compound that is used as a key medication in treating Parkinson’s disease (PD), particularly in managing bradykinetic symptoms of the disorder. Despite its nontoxicity in humans, there has been concern that high doses of L-DOPA may worsen the symptoms of peripheral neuropathy (PN) that commonly occurs in PD patients. PN is manifested in changes in peripheral sensation, weakness, and postural instability and is increasingly understood to contribute to the overall level of disability of PD patients. Here, we aimed to investigate whether high-dose L-DOPA impaired sensory function in mice. Instead of a Parkinsonian model, which is likely to cause complex changes in the skin, the unpredictable chronic mild stress (UCMS) model was used in combination with L-DOPA to assess whether L-DOPA exacerbated sensory changes caused by UCMS. In order to assess sensory function, gold-standard validated test protocols were used, including Hargreaves, tail flick, cold plantar and von Frey with a novel hot-and-cold-exploration test. The required group sizes were calculated based on pilot experiments. Our results were intriguing: mice receiving high doses of L-DOPA were more sensitive to touch and cold but less sensitive to heat. Importantly, administration of vitamin B12 prevented these sensory changes. These findings show that L-DOPA induces sensory impairments in vivo, and critically, vitamin B12 can offset these negative effects. Vitamin B12 is well known in the clinic, but controversy exists over whether it should be used with L-DOPA. Our data suggest that it should. Given that peripheral changes in sensation may contribute to overall motor impairment in PD, our data highlights the deleterious effects of L-DOPA and also the benefits of supplementing L-DOPA treatment with neuroprotective compounds like vitamin B12 to improve patient outcomes.
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    Study of Transformation Methods for Chemically Competent E. coli Cells
    (Tartu Ülikool, 2024) Agbakwa, Uchechi Martina; Sarıgül, İsmail, juhendaja; Maiväli, Ülo; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Bacterial transformation is the ability of bacteria to uptake foreign DNA. High transformation efficiencies (TEs) are important in various molecular cloning processes, DNA library construction and transformation of large plasmids. Therefore, common laboratory strains are made competent by treating their membranes to enhance plasmid uptake. Transformation and storage solution (TSS) is a buffer for making common laboratory E. coli competent cells. (Chung et al., 1989). Two recent studies have reported one to two-log improved TEs (Yang, Liu, et al., 2022; Yang, Yu, et al., 2022), using slightly modified transformation buffers (TSS or TSS-HI) and methods (KCM or Heat shock). Here, we intend to reproduce these two improved methods. We prepared chemically competent E. coli cells using TSS or TSS-HI buffers. The competent cells were transformed using KCM, heat shock, or heat shock + KCM methods. Results revealed that E. coli strains washed with the modified TSS and TSS-HI buffers and transformed via different methods did not exhibit any significant improvement or difference in the transformation efficiency. However, the modified protocols produce competent cells suitable for quick transformation, eliminating the need for incubation on ice (usually 30 minutes) or recovery (about 1 hour). Our findings refute the reported modifications' effectiveness, reliability, and reproducibility in improving TEs.
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    Exploring the impact of small-molecule compounds on human papillomavirus type 5 replication and host cell differentiation
    (Tartu Ülikool, 2024) Zaikina, Lidiia; Lototskaja-Perepelenko, Elina, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    Human papillomavirus (HPV) is the most widely spread sexually transmitted virus worldwide. Different types of HPVs can cause skin lesions and cancers. HPV5 belongs to beta papillomavirus and is commonly found in healthy skin, while also associated with skin cancer in patients with immune deficiency or a genetic disorder, Epidermodysplasia verruciformis. Vaccines preventing infection with the most carcinogenic mucosal HPV types exist, but they are inefficient against cutaneous HPVs. Also, there is no effective treatment for existing infections, which emphasizes the need to develop antiviral drugs. The present thesis focuses on two small-molecule compounds (#1 and #2) identified through a high-throughput screening performed prior to this study. The aim was to confirm their inhibitory effect on HPV5 replication and to determine the effect of the identified inhibitors on the differentiation of human osteosarcoma (U2OS) cells and human primary epithelial keratinocytes (HPEKs), which are used as HPV model host cells. Both compounds showed a strong inhibitory effect on the HPV5 replication in U2OS cells, and the inhibitory activity of the compound #2 was confirmed also in HPEKs. However, in contrast to the compound #2, the compound #1 upregulated the HPV5 replication in HPEKs, which was explained by the differentiation-inducing effect. Thus, the compound #2 was chosen as a potential HPV5 replication inhibitor for future investigation.
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    Audio System for the Social Humanoid Robot SemuBot
    (Tartu Ülikool, 2024) Nizamov, Timur; Kruusamäe, Karl, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    A huge and important part of a human companion robot is related to communication abilities. The humanoid robot should be able to hear the incoming speech, understand it and respond to it in the direction of a human that starts the interaction. To provide for such a solution, this thesis focuses on the design, testing and implementation of such a sound system for a real human companion robot. The proposed sound system is composed of a microphone array board, a speaker system, a digital amplifier, and the Arduino MEGA for testing amplifier volume gain. Additionally, the ROS2 Humble is utilised for uniting the coded scripts and better communication with other parts of the robot. The result of this work is shown on a real robot and together with other team members presented as a working prototype.
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    Heat shock and chemical-induced stress response of Pseudomonas putida strains
    (Tartu Ülikool, 2024) Grigorjeva, Jūlija; Jõesaar, Merike, juhendaja; Viggor, Signe, juhendaja; Tartu Ülikool. Loodus- ja täppisteaduste valdkond; Tartu Ülikool. Tehnoloogiainstituut
    The C1 chemicals, such as formate and methanol, are potential feedstocks for sustainable bioproduction. This thesis investigates whether microorganisms that have been genetically modified to assimilate these substances through the reductive glycine pathway face stress. The growth experiments in C1 substrates under heat shock and chemical stress conditions by using stress response reporter systems, pAG032 and pBSibp_Amp, were performed. pBSibp_Amp is a better choice for measuring the heat shock response because it gives much higher ratios than pAG032, and fluorescent bacterial proteins, naturally produced by P. putida and the red fluorescent protein’s fluorescence spectra from plasmid do not overlap. Genetically modified strains can tolerate high concentrations of methanol and formate but do not yield biomass in these growth conditions.