A circular dichroism study of the stability of guanine quadruplexes of thrombin DNA aptamers at presence of K+ and Na+ ions

The effect of K+ and Na+ on the properties of DNA aptamers that selective binds to fibrinogen (FIBRI) and heparin (HEPA) exosites of human alpha-thrombin was studied by circular dichroism (CD). The complexes of FIBRI-K+ were slightly more stable than HEPA-K+. However, lower stability was observed fo...

Full description

Saved in:
Bibliographic Details
Published in:General physiology and biophysics 2008-12, Vol.27 (4), p.271-277
Main Authors: Poniková, Slavomíra, Antalík, Marián, Hianik, Tibor
Format: Article
Language:English
Subjects:
Aptamers, Nucleotide - chemistry
Cations - chemistry
Circular Dichroism - methods
Fibrinogen - chemistry
G-Quadruplexes
Heparin - chemistry
Humans
Potassium - chemistry
Sodium - chemistry
Thrombin - chemistry
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The effect of K+ and Na+ on the properties of DNA aptamers that selective binds to fibrinogen (FIBRI) and heparin (HEPA) exosites of human alpha-thrombin was studied by circular dichroism (CD). The complexes of FIBRI-K+ were slightly more stable than HEPA-K+. However, lower stability was observed for HEPA-K+ at presence of Na+ in comparison with FIBRI-K+. The analysis of CD melting curves suggests differences in thermal stability of both aptamers at presence of K+. The melting temperatures (Tm) and changes in van't Hoff enthalpy for HEPA-K+ complexes were lower in comparison with those for FIBRI-K+. With increasing HEPA concentration the Tm value increased, but Tm did not change with increasing FIBRI concentration. This suggests formation of HEPA aggregates, while FIBRI aptamers are in monomeric form.
ISSN:0231-5882