Bakterijske i virusne makrodomene – struktura, funkcija i terapeutski potencijal

doctoral thesis

• Title (english): Bacterial and viral macrodomains - structure, function and therapeutic potential
• Author: Andrea Hloušek-Kasun
• Mentor: Andreja Mikoč (mentor)
• Mentor: Branimir Bertoša (mentor)
• Committee member: Marko Močibob (predsjednik povjerenstva)
• Committee member: Sanja Tomić (član povjerenstva)
• Committee member: Branka Salopek-Sondi (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2023-03-23, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry
• Universal decimal classification (UDC): 54 - Chemistry. Crystallography. Mineralogy

Abstract

ADP-ribozilacija je kovalentna modifikacija koja kontrolira brojne važne stanične procese od
bakterija do čovjeka. ADP-ribozilacijski sustav čine ADP-ribozil-transferaze koje prenose ADPribozu na ciljnu (makro)molekulu i ADP-ribozil-hidrolaze koje osiguravaju reverzibilnost procesa.
Glavni predstavnici ADP-ribozil-hidrolaza su makrodomenski proteini zastupljeni u sve tri
domene života uključujući i viruse. U ovom doktorskom radu istraživana su dva makrodomenska
proteina, SCO6735 iz bakterije Streptomyces coelicolor i Mac1 iz virusa SARS-CoV-2. Pokazano
je da SCO6735 uklanja ADP-ribozilaciju s jednolančane DNA modificirane na timinu. Na temelju
računalnih i eksperimentalnih rezultata predložen je novi katalitički mehanizam hidrolize ADPriboze s DNA karakterističan za skupinu proteina sličnih SCO6735. Makrodomena Mac1 inhibira
imunološki odgovor domaćina čime potiče virusnu replikaciju. Stoga ima terapeutski potencijal za
liječenje bolesti uzrokovane virusom SARS-CoV-2. U tu svrhu provedena je virtualna pretraga
baze malih molekula koja je rezultirala testiranjem 27 spojeva metodom izotermalne titracijske
kalorimetrije. Izmjereni afiniteti vezanja potvrdili su dobro vezanje nekoliko spojeva, uključujući
FDA-odobrene lijekove Dasatinib i Metotreksat.

Abstract (english)

ADP-ribosylation is a covalent modification that controls essential cellular processes, conserved
from bacteria to humans. The ADP-ribosylation system consists of ADP-ribosyl transferases that
catalyse the transfer of ADP-ribose to a target (macro)molecule, while ADP-ribosyl hydrolases
ensure reversibility. Macrodomain proteins are ADP-ribosyl hydrolases present in all three
domains of life and viruses. In this dissertation, two macrodomain proteins were investigated:
SCO6735 from Streptomyces coelicolor and Mac1 encoded by the virus SARS-CoV-2. SCO6735
was experimentally shown to act antagonistically to a bacterial toxin known to impair replication
by ADP -ribosylation of thymidines in single-stranded DNA. Furthermore, a novel catalytic
mechanism of DNA-(ADP-ribose) hydrolysis characteristic of the subgroup of SCO6735-related
proteins was proposed. The Mac1 macrodomain is a good therapeutic target, because it inhibits
the host immune response, thus allowing virus replication. In search of potential inhibitors, a
virtual screening of a compound library was performed. The screening resulted in testing of 27
molecules with the isothermal titration calorimetry. Determined binding affinities suggested good
binding of several molecules, including the FDA-approved drugs Dasatinib and Methotrexate.

• Keywords: ADP-ribozilacija; makrodomenski proteini; protein SCO6735; makrodomena Mac1; Streptomyces coelicolor; virus SARS-CoV-2
• Keywords (english): ADP-ribosylation; macrodomain proteins; 6735 protein; Mac1 macrodomain/; Streptomyces coelicolor; SARS-CoV-2 virus
• Language: croatian
• URN:NBN: urn:nbn:hr:217:629915
• Promotion: 2023
• Study programme: Title: Doctoral study in chemistry; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija (doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija)
• Type of resource: Text
• Extent: XV, 134 str ; 30 cm
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-11-23
• Created on: 2023-04-03 13:03:34