Bissenbayev, Kudaybergen2024-06-052024-06-052024-04-11Bissenbayev, K. (2024). Functional Characterization Of Osmotic Stress Response In Haloarchaea Isolated From The Kobeituz Lake. Nazarbayev University School of Sciences and Humanitieshttp://nur.nu.edu.kz/handle/123456789/7748Halobacterium KBTZ01, a halophile archaea species from Kobeituz Lake, Kazakhstan, thrives in hypersaline environments. Therefore, these serve as good models for studying molecular mechanisms underlying the tolerance to high salt concentrations. This study investigates the impact of osmotic stress on these cells, induced by exposure to varying NaCl concentrations (0.6/1/1.5M) in a hypotonic growth medium at 3 and 9 hours. The experimental approach involves studying stress response by incubating cells in hypotonic media, followed by protein extraction and analysis using SDS-PAGE and mass spectrometry. The morphology and viability parameters were analyzed with confocal microscopy. Low NaCl concentrations (600) are deadly for the haloarchaea, while 1M and 1.5M NaCl can be tolerated for a certain amount of time. Proteomic findings include upregulation of certain proteins related to metabolism, biogenesis and signal processing. Significant decrease in motility was observed and was validated by downregulation of motility proteins. Some proteins indicate varying abundance levels with progression of hypotonic stress. This research contributes valuable insights into the molecular mechanisms enabling halophilic archaea to thrive in challenging environments.en-USAttribution-NonCommercial-NoDerivs 3.0 United Stateshaloarchaea, proteomics, Kobeituz, archaeaType of access: RestrictedhaloarchaeaproteomicsKobeituzarchaeaBachelor's thesis