a 2011

A Study of Cytosine Oligonucleotides by Voltammetric and Spectral Methods

BALCAROVÁ, Zdeňka, Sylvie HOLUBOVÁ, Radka CHALOUPKOVÁ and Libuše TRNKOVÁ

Basic information

Original name

A Study of Cytosine Oligonucleotides by Voltammetric and Spectral Methods

Authors

BALCAROVÁ, Zdeňka (203 Czech Republic, belonging to the institution), Sylvie HOLUBOVÁ (203 Czech Republic, belonging to the institution), Radka CHALOUPKOVÁ (203 Czech Republic, belonging to the institution) and Libuše TRNKOVÁ (203 Czech Republic, guarantor, belonging to the institution)

Edition

Biopolymers: Structure and dynamics, A biophysical workshop, 2011

Other information

Language

English

Type of outcome

Konferenční abstrakt

Field of Study

10403 Physical chemistry

Country of publisher

Czech Republic

Confidentiality degree

není předmětem státního či obchodního tajemství

RIV identification code

RIV/00216224:14310/11:00053671

Organization unit

Faculty of Science

ISBN

978-80-263-0050-2

Keywords in English

oligonucleotides;linear sweep voltammetry;elimination voltammetry with linear scan;LSV;EVLS;cirkular dichroism;cytosine

Tags

Změněno: 13/4/2012 12:31, prof. RNDr. Libuše Trnková, CSc.

Abstract

V originále

For the study of three short homo–deoxyoligonucleotides (homo–ODNs) containing cytosine – dC3 , dC6 and dC9 – we used electrochemical and spectral methods. Using linear sweep voltammetry (LSV) and elimination voltammetry with linear scan (EVLS) the effect of pH and the number of C in the ODN chain on reduction signals in buffered solutions was investigated.1-2 The reduction C peaks, recorded at hanging mercury drop electrode (HMDE) in the potential range from –1.0 V to –1.7 V vs. Ag/AgCl/3 M KCl, are strongly dependent not only on pH but also on the composition of solutions. The measurements were done in phosphate – acetate buffer (0.08 M) with the addition of 0.1M NaCl in pH range from 1.55 to 8.57. The concentration of all ODN was 10 uM. From acidic to alkaline pH scale, three reduction ranges were found. For dC3, dC6 and dC9 we observe on voltammetric curves a shift of the reduction peaks towards more negative potentials with increasing pH and increasing scan rate. It was found that: (a) the peak heights of all ODNs are roughly the same in a range from pH 4 to 6, (b) around pH of 6.5 dC3 provided a double peak which disappeared at higher pHs and one reduction peak was observed, (c) the peak heights of dC6 and dC9 decreased from pH 6.5 to 7.10 resulting in double peaks at higher pH. The different voltammetric behavior of ODNs was confirmed by circular dichroism (CD) spectroscopy, which reveals that the structure of dC6 and dC9 undergoes conformational changes under alkaline conditions, whereas the structure dC3 remainst unchanged. The possible explanation consists in the formation of an i-motif where four dC3 molecules form a very stable associate. The stability of ODNs will be the subject of our future investigation. The occurrence of this unusually stable i-motif is interesting because ODNs as important components of nucleic acids can play a crucial role in the process of genetic information transfer.

Links

LC06035, research and development project
Name: Centrum biofyzikální chemie, bioelektrochemie a bioanalýzy. Nové nástroje pro genomiku, proteomiku a biomedicínu.
Investor: Ministry of Education, Youth and Sports of the CR, Centre of Biophysical Chemistry, Bioelectrochemistry and Bioanalysis. New Tools for Genomics, Proteomics and Biomedicine
MSM0021622412, plan (intention)
Name: Interakce mezi chemickými látkami, prostředím a biologickými systémy a jejich důsledky na globální, regionální a lokální úrovni (INCHEMBIOL) (Acronym: INCHEMBIOL)
Investor: Ministry of Education, Youth and Sports of the CR, Interactions among the chemicals, environment and biological systems and their consequences on the global, regional and local scales (INCHEMBIOL)
MUNI/A/0992/2009, interní kód MU
Name: Vývoj metodologie a instrumentace analytické chemie pro studium složení a vlastností přírodních a syntetických materiálů (Acronym: MIA)
Investor: Masaryk University, Category A