Spektroskopska karakterizacija dipeptida pirena i cijanina i njihove interakcije s dvolančanim polinukleotidima

master's thesis

• Title (english): Spectroscopic characterization of pyrene-cyanine dipeptides and their interactions with double-stranded polynucleotides
• Author: Marko Badovinac
• Mentor: Ivo Piantanida (mentor)
• Committee member: Gordan Horvat (predsjednik povjerenstva)
• Committee member: Snežana Miljanić (član povjerenstva)
• Committee member: Morana Dulić (član povjerenstva)
• Committee member: Davor Kovačević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2019-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Pireni i cijanini poznate su fluorescentne probe. Pireni se često koriste za praćenje konformacijskih
promjena proteina kovalentno vezanih na njih dok se cijanini, intrinzično nefluorescentni, odlikuju
izrazitom fluorescencijom prilikom vezanja na biološke mete kao što su proteini ili nukleinske kiseline.
U sklopu ovog diplomskog rada proučavana su dva novosintetizirana i do sad nepoznata izomera
dipeptida pirena i cijanina. Prvo su ispitana njihova spektroskopska svojstva, temperaturna stabilnost te
uvjeti agregiranja UV/Vis spektroskopijom. Potom su ispitane interakcije dvaju izomera s dvolančanim
polinukleotidima različitih slijedova baza i sekundarnih struktura. Obradom fluorimetrijskih titracija
dobivene su konstante stabilnosti kompleksa s polinukleotidima te ovisnost intenziteta emisije o
sekundarnoj strukturi polinukleotida. Način vezanja spojeva na polinukleotide određen je
spektroskopijom cirkularnog dikroizma, dok je utjecaj na stabilizaciju dvolančane uzvojnice određen
spektroskopski određivanjem temperature mekšanja kompleksa. Dobiveni rezultati ukazuju na biološki
relevantne interakcije novih spojeva s DNA i RNA.

Abstract (english)

Pyrenes and cyanines are known fluorescent probes. Pyrenes are often used to monitor the
conformational changes of proteins by covalently bound to them, whereas cyanins, intrinsically nonfluorescent,
are characterized by a pronounced fluorescence emission when bound to biological targets
such as proteins or nucleic acids. Two newly synthesized and still unknown isomers of pyrene and
cyanine dipeptides were studied as part of this thesis. First, their spectroscopic properties, temperature
stability, and aggregation conditions by UV/Vis spectroscopy were examined. The interactions of the
two isomers with double-stranded polynucleotides of different base sequences and secondary structures
were then examined. Treatment with fluorimetric titrations obtained the stability constants of the
complex with polynucleotides and the dependence of the emission intensity on the secondary structure
of the polynucleotides. The mode of binding compounds to polynucleotides was determined by
spectroscopy of circular dichroism, while the influence on stabilization of the double-stranded helix was
determined spectroscopically by determining the melting temperature of the complex. The results
obtained indicate the biologically relevant interactions of new compounds with DNA and RNA.

• Keywords: cirkularni dikroizam; dipeptidi pirena i cijanina; fluometrijske titracije; fluorescentne probe; nukleinske kiseline; temperatura mekšanja
• Keywords (english): circular dichroism; fluorescent probes; fluorimetric titrations; nucleic acids; pyrene-cyanine dipeptides; melting temperature
• Language: croatian
• URN:NBN: urn:nbn:hr:217:918142
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-09-30 12:31:03