Adaptivna laboratorijska evolucija bakterije Geobacillus thermoglucosidasius u uvjetima ekstremnog okoliša

master's thesis

• Title (english): Adaptive laboratory evolution of bacterium Geobacillus thermoglucosidasius in extreme enironmental conditions
• Author: Ivana Saraga
• Mentor: Ivan Mijaković (mentor)
• Mentor: Damjan Franjević (komentor)
• Committee member: Damjan Franjević (predsjednik povjerenstva)
• Committee member: Tomislav Ivanković (član povjerenstva)
• Committee member: Goran Klobučar (član povjerenstva)
• Committee member: Josip Skejo (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2024-09-02, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Kako bi se smanjila koncentracija CO2 u zraku, znanstvenici pokušavaju koristiti bakterije kao stanične tvornice koje bi hvatale dodatni CO2 te pomoću procesa mineralizacije ga “reciklirale” i kasnije koristili u različitim granama industrije. Ovaj rad se bazira na adaptivnoj laboratorijskoj evoluciji tri soja bakterije Geobacillus thermoglucosidasius. Ova termofilna i gram-pozitivna bakterija može rasti pri maksimalnoj vrijednosti pH od 8.5 te temperaturi od 70°C. U ovom je istraživanju provedena adaptivna laboratorijska evolucija na okoliš gdje prevladava alkalni pH (>8.5) te temperatura viša od 70°C: uvjeti koji odgovaraju ugljičnoj anhidrazi. To je esencijalno jer je jednom od korištenih sojeva pomoću genetske modifikacije ugljična anhidraza, enzim koji hvata ugljik, pričvršćena za staničnu stijenku. Također, jedan je od ciljeva bio i usporediti efikasnost protokola rađenog ručno s automatiziranim protokolom. Rezultati su pokazali 4 zajedničke mutacije na genima šest replika dobivenih ručno rađenim protokolom zbog adaptacije na pH 9.1. Replike dobivene automatiziranim protokolom su imale 4 zajedničke mutacije na jednoj skupini sojeva i 1 na drugoj. Dostignuti pH je 9.01. Adaptivna laboratorijska evolucija se još jednom dokazala korisnom za optimizaciju staničnih tvornica za industrijsku upotrebu te se ručno rađeni protokol dokazao efikasnijim od automatiziranog.

Abstract (english)

To fight high CO2 emissions scientists are trying to use bacteria as cell factories to capture extra CO2 via mineralisation to “recycle” it and use it in different industries. This study aimed to use adaptive laboratory evolution on three strains of Geobacillus thermoglucosidasius. This thermophilic and gram-positive bacterium can grow at a maximum of 8.5 pH and 70°C temperature. One of the strains was genetically modified to express a carbonic anhydrase, the enzyme that enables carbon capture, anchored to its cell wall. The goal was to adapt these strains to an environment that is defined by alkaline pH (> 8.5) and temperature higher than 70°C: the conditions that favour carbonic anhydrase activity. We also wanted to compare the efficiency of a manually performed protocol versus automation. The results demonstrated 4 common mutations among 6 manually executed replicates that managed to adapt to 9.1 pH. Automatically performed replicates reached a maximum pH of 9.01 and had 4 common mutations for one set of replicates and 1 common mutation for the second set. Overall, adaptive laboratory evolution once more proved useful for optimizing cell factories for industrial applications and the manual protocol performed better than the automatic one.

• Keywords: Geobacillus thermoglucosidasius; ALE; klimatske promjene; alkalni pH
• Keywords (english): ALE; Geobacillus thermoglucosidasius; alkaline pH; climate change
• Language: english
• URN:NBN: urn:nbn:hr:217:147622
• Study programme: Title: Experimental Biology-University graduate programme; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra eksperimentalne biologije (sveučilišni/a magistar/magistra eksperimentalne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2025-09-02
• Created on: 2024-09-16 15:52:33