Ionization state and molecular docking studies for the macrophage migration inhibitory factor: The role of lysine 32 in the catalytic mechanism

T. A. Soares, D. S. Goodsell, R. Ferreira, A. J. Olson, J. M. Briggs

Research output: Contribution to journalArticle

28 Scopus citations


The macrophage migration inhibitory factor (MIF) is a cytokine that is structurally similar to certain isomerases and for which multiple immune and catalytic roles have been proposed. Different catalytic activities have been reported for MIF, yet the exact mechanism by which MIF acts is not completely known. As a tautomerase, the enzyme uses a general acid-base mechanism of proton transfer in which the amino-terminal proline has been shown to function as the catalytic base. We report the results of molecular docking simulations of macrophage migration inhibitory factor with three substrates, D-dopachrome, L-dopachrome methyl ester and p-(hydroxyphenyl)pyruvate. Electrostatic pK(a) predictions were also performed for the free and complexed forms of the enzyme. The predicted binding mode of p(hydroxyphenyl)pyruvate is in agreement with the recently published X-ray structure. A model for the binding mode of D-dopachrome and L-dopachrome methyl ester to MIF is proposed which offers insights into the catalytic mechanism of D-dopachrome tautomerase activity of MIF. The proposed catalytic mechanism is further supported by the pK(a) predictions, which suggest that residue Lys32 acts as the general acid for the enzymatic catalysis of D-dopachrome. Copyright (C) 2000 John Wiley and Sons, Ltd.

Original languageEnglish (US)
Pages (from-to)146-156
Number of pages11
JournalJournal of Molecular Recognition
Issue number3
StatePublished - May 1 2000
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Structural Biology
  • Molecular Biology


  • Catalytic mechanism
  • Lamarckian genetic algorithm molecular docking
  • Macrophage migration inhibitory factor
  • Poisson-Boltzmann electrostatics
  • pK(a) studies

Cite this