Original scientific paper

Probing of the Surface of High-Density Lipoproteins with Mn(II) Ions and EPR Spectroscopy

Jasminka Brnjas-Kraljević ; School of Medicine, University of Zagreb, Zagreb, Croatia
Greta Pifat ; Rudjer Bošković Institute
Janko Herak ; Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia

Abstract

Negatively charged sites on the surface of two human high-density lipoproteins, HDL2 and HDL3, have been studied using EPR spectroscopy. Like for LDL, there are two types of binding sites for the Mn(II) ions on each HDL class, characterized by essentially the same binding constants as those for LDL. The small number of »strong« sites (n = 2), attributed to the negatively charged amino-acid residues, indicates that only a small fraction of these residues is available for cation binding. The binding constants for »weak« sites and the number of these sites in LDL and in the two HDL subfractions studied are consistent with the idea that these sites relate to the phospholipid domains on the lipoprotein surface.

Keywords

Hrčak ID:

137056

URI

https://hrcak.srce.hr/137056

Publication date:

1.3.1994.

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