Zinc binding reverses the calcium‐induced arachidonic acid‐binding capacity of the S100A8/A9 protein complex

FEBS Letters

Vogl, Thomas¹  Nacken, Wolfgang¹  Kerkhoff, Claus¹  Sopalla, Claudia¹  Sorg, Clemens¹ 

[1] Institute of Experimental Dermatology, von-Esmarch-Str. 56, 48149 Münster, Germany

关键词: Arachidonic acid;    Ca2+ binding protein;    Ca2+;    Cu2+;    Fatty acid binding protein;    Protein structure;    Zn2+;    AA;    arachidonic acid;    FMLP;    formylmethionylleucylphenylalanine;    GST;    glutathione S-transferase;   

DOI  :  10.1016/S0014-5793(99)01322-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Analysis of the calcium-induced arachidonic acid (AA) binding to S100A8/A9 revealed that maximal AA binding was achieved at molar ratios of 1 mol S100A8 and 1 mol S100A9 and for values greater than 3 calciums per EF-hand. The AA binding capacity was not induced by the binding of other bivalent cations, such as Zn²⁺, Cu²⁺, and Mg²⁺, to the protein complex. In contrast, the binding of AA was prevented by the addition of either Zn²⁺ or Cu²⁺ in the presence of calcium, whereas Mg²⁺ failed to abrogate the AA binding capacity. The inhibitory effect was not due to blocking the formation of S100A8/A9 as demonstrated by a protein-protein interaction assay. Fluorescence measurements gave evidence that both Zn²⁺ and Cu²⁺ induce different conformational changes thereby affecting the calcium-induced formation of the AA binding pocket within the protein complex. Due to the fact that the inhibitory effect of Zn²⁺ was present at physiological serum concentrations, it is assumed that released S100A8/A9 may carry AA at inflammatory lesions, but not within the blood compartment.

【 授权许可】

Unknown