Preživljavanje ljubičastih nesumpornih bakterija (Rhodobacter azotoformans JCM 9340 i Rhodobacter capsulatus JCM 21090) pri različitim koncentracijama soli

undergraduate thesis

• Title (english): Survival of purple non-sulfur bacteria (Rhodobacter azotoformans JCM 9340 and Rhodobacter capsulatus JCM 21090) at different salt concentrations
• Author: Ana Vadoc
• Mentor: Iva Čanak (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for General Microbiology and Food Microbiology); Zagreb
• Defense date and country: 2023-09-08, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Ljubičaste bakterije velika su podgrupa fotosintetskih mikroorganizama i provode fotosintezu bez proizvodnje kisika. Dijele se na ljubičaste sumporne i nesumporne bakterije. Izoliraju se iz vodenih staništa poput jezera, ribnjaka ili otpadnih voda te iz sedimenata i vlažnog tla. Ove bakterije važne su u biotehnološkoj proizvodnji zbog svog ekološkog i ekonomskog značaja. Njihova primjena zabilježena je u proizvodnji biokemikalija, biopolimera, biogoriva, kod sinteze pigmenata, obrade otpadnih voda i bioremedijacije tla. Ljubičaste bakterije poznati su halofili te je cilj ovog istraživanja bilo ispitati kako dvije vrste ljubičastih nesumpornih bakterija, Rhodobacer azotoformans JCM 9340 i Rhodobacter capsulatus JCM 21090, preživljavaju uz dodatak NaCl-a, te kako dodatak soli utječe na ekspresiju ukupnih proteina. Rezultati su pokazali kako obje vrste uspješno preživljavaju u velikom broju stanica pri svim ispitanim koncentracijama soli, i to R. azotoformans u rasponu od 10⁵ -10⁸ CFU/ml, a R. capsulatus od 10⁵ -10⁷ CFU/ml. Analizom na proteinskoj razini pomoću SDS elektroforeze utvrđeno je da dodatak NaCl smanjuje ekspresiju proteina što je vidljivo iz odsustva proteinskih vrpci u uzorcima s dodanom soli. Potrebna su dodatna istraživanja kako bi se utvrdilo koji je mehanizam točno odgovoran za preživljavanje ljubičastih nesumpornih bakterija u ekstremnim uvjetima.

Abstract (english)

Purple bacteria are a large subgroup of photosynthetic microorganisms and carry out photosynthesis without the production of oxygen. They are divided into purple sulfur and non-sulfur bacteria. They are isolated from aquatic habitats such as lakes, ponds or wastewater, as well as from sediments and moist soil. These bacteria are important in biotechnological production due to their ecological and economic importance. Their application has been noted in the production of biochemicals, biopolymers, biofuels, in the synthesis of pigments, wastewater treatment and soil bioremediation. Purple bacteria are known halophiles, and the aim of this research was to examine how two types of purple non-sulfur bacteria - Rhodobacer azotoformans JCM 9340 and Rhodobacter capsulatus JCM 21090 survive with the addition of NaCl, and how the addition of salt affects the expression of total proteins. The results showed that both species successfully survive in a large number of cells at all tested salt concentrations, R. azotoformans in the range of 10⁵ -10⁸ CFU/ml and R. capsulatus in the range of 10⁵ - 10⁷ CFU/ml. Analysis at the protein level using SDS electrophoresis revealed that the addition of NaCl reduces protein expression, which is evident from the absence of protein bands in samples with added salt. Further research is needed to determine exactly what mechanism is responsible for the survival of purple non-sulfur bacteria in extreme conditions.

• Keywords: ljubičaste nesumporne bakterije; inhibicija rasta; sol
• Keywords (english): purple non-sulfur bacteria; growth inhibition; salt
• Language: croatian
• URN:NBN: urn:nbn:hr:159:468891
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-04-29 13:18:21