These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Effects of ionic strength, temperature and conformation on affinity interactions of β₂-glycoprotein I monitored by capillary electrophoresis.
    Author: Bohlin ME, Blomberg LG, Heegaard NH.
    Journal: Electrophoresis; 2011 Mar; 32(6-7):728-37. PubMed ID: 21365655.
    Abstract:
    We have used CE to evaluate the interaction between β₂-glycoprotein I (β₂gpI) and heparin. β₂gpI is a human plasma protein involved in the blood coagulation cascade. It is of interest to functionally characterize the interactions of β₂gpI because the exact function is not entirely known and because circulating autoantibodies against β₂gpI are associated with an increased risk of thrombotic events. The effect of the ionic strength, temperature, and conformation of the protein on the interaction between β₂gpI and heparin has been studied. The CE procedure for this study is simple, fast, and automatic. β₂gpI and heparin were allowed to interact during electrophoresis at different ionic strength buffers and at different capillary temperatures. To mimic perturbation of the conformation of β₂gpI, different denaturing agents (SDS, ACN, and urea) were added to the BGE. While simple 1:1 binding isotherms were obtained at 22 °C, the data strongly suggest that at physiological temperature the binding stoichiometry is not 1:1 and/or that cooperative interactions begin to play a role. We found that (i) the K(D)-values differed by a factor of 60 at the ionic strengths studied (ii) β₂gpI was resistant to denaturation with SDS and ACN, but was partially denatured by urea, and (iii) the K(D) for the β₂gpI-heparin interaction in the presence of urea was ten times higher than the K(D) determined at the same conditions without urea added. Therefore, we conclude that the interaction between β₂gpI and heparin is dependent on electrostatic interactions and on the conformation of β₂gpI.
    [Abstract] [Full Text] [Related] [New Search]