New aspects of enzymes working in lignocellulose degradation

master's thesis

• Title (english): Novi aspekti enzima koji sudjeluju u razgradnji lignoceluloze
• Author: Marija Hanžek
• Mentor: Božidar Šantek (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2017-12-08, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Fossil fuels have to be replaced by renewable energies (e.g. biomass) due to increasing global demand for energy. The discovery of LPMOs (lytic polysaccharide monooxygenases) was a breakthrough in understanding of how nature degrades biomass. The main obstacle in LPMO research is the lack of an easy to use spectroscopic activity assay. Accordingly, the aim of this thesis was to develop and validate an activity assay and concomitantly characterize the LPMO from the fungi Neurospora crassa. 2,6-DMP (2,6-dimethoxyphenol) as reductant in addition with the new cosubstrate H2O2 was proven to be the best chromogenic compound with a high extinction coefficient (24.8 mM-1cm-1) in the visible range (469 nm). The optimal LPMO activity was observed in the neutral to basic pH range. The lowest concentration of LPMO, which could be measured and distinguished from blank reactions, was ~0.0125 μM.

Abstract (english)

Zbog povećane globalne potražnje za energijom, fosilne izvore potrebno je zamijeniti obnovljivim izvorima energije (npr. biomasom). Otkriće LPMO (litičke polisaharid monooksigenaze) bilo je ključno za razumijevanje prirodne razgradnje biomase. Glavna prepreka u istraživanju LPMO je nedostatak jednostavnog protokola za istraživanje enzimske aktivnosti pomoću spektroskopije. Sukladno tome, cilj ovog rada bio je razviti i potvrditi protokol za utvrđivanje enzimske aktivnosti te istodobno okarakterizirati LPMO izoliranu iz plijesni Neurospora crassa. Dokazano je da je reduktant 2,6-DMP (2,6-dimetoksifenol), zajedno sa novootkrivenim kosupstratom H2O2, najbolja kromogenska komponenta sa visokim molarnim apsorpcijskim koeficijentom (24.8 mM-1cm-1) u vidljivom dijelu spektra (469 nm). Optimalna aktivnost LPMO je u neutralnom prema bazičnom pH području. Najniža koncentracija LPMO koja može biti izmjerena i koja se razlikuje od vrijednosti slijepe probe je ~0.0125 μM.

• Keywords: LPMO; 2; 6-dimethoxyphenol; hydrogen peroxide; assay; spectrophotometry
• Keywords (english): LPMO; 2; 6-dimetoksifenol; vodikov peroksid; analiza; spektrofotometrija
• Language: english
• URN:NBN: urn:nbn:hr:159:913919
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-11-15 11:24:41