Structural Study of the Complex Formed by Ceruloplasmin and Macrophage Migration Inhibitory Factor

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A. V. Sokolov^1,2,3,4#, L. A. Dadinova^5#, M. V. Petoukhov^5,6,7,8, G. Bourenkov⁶, K. M. Dubova⁵, S. V. Amarantov⁵, V. V. Volkov⁵, V. A. Kostevich^1,2, N. P. Gorbunov¹, N. A. Grudinina¹, V. B. Vasilyev^1,3, and V. R. Samygina^5,9,a*

¹Institute of Experimental Medicine, 197376 St. Petersburg, Russia

²Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia

³St. Petersburg State University, 199000 St. Petersburg, Russia

⁴Center of Preclinical Translational Research, Almazov National Medical Research Center, 197371 St. Petersburg, Russia

⁵Shubnikov Institute of Crystallography, FSRC “Crystallography and Photonics”, Russian Academy of Sciences, 119333 Moscow, Russia

⁶European Molecular Biology Laboratory (EMBL), 22607 Hamburg, Germany

⁷Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119071 Moscow, Russia

⁸Semenov Institute of Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia

⁹National Research Center “Kurchatov Institute”, 123182 Moscow, Russia

^# These authors contributed equally to this work.

^* To whom correspondence should be addressed.

Received November 1, 2017; Revision received February 2, 2018

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Macrophage migration inhibitory factor (MIF) is a key proinflammatory cytokine. Inhibitors of tautomerase activity of MIF are perspective antiinflammatory compounds. Ceruloplasmin, the copper-containing ferroxidase of blood plasma, is a noncompetitive inhibitor of tautomerase activity of MIF in the reaction with p-hydroxyphenylpyruvate. Small-angle X-ray scattering established a model of the complex formed by MIF and ceruloplasmin. Crystallographic analysis of MIF with a modified active site supports the model. The stoichiometry of 3 CP/MIF trimer complex was established using gel filtration. Conformity of novel data concerning the interaction regions in the studied proteins with previous biochemical data is discussed.

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KEY WORDS: X-ray analysis, small-angle X-ray scattering, protein–protein interactions, ceruloplasmin, macrophage migration inhibitory factor

DOI: 10.1134/S000629791806007X

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