1MFI

CRYSTAL STRUCTURE OF MACROPHAGE MIGRATION INHIBITORY FACTOR COMPLEXED WITH (E)-2-FLUORO-P-HYDROXYCINNAMATE

1MFI の概要

• エントリーDOI: 10.2210/pdb1mfi/pdb
• 分子名称: PROTEIN (MACROPHAGE MIGRATION INHIBITORY FACTOR), 2-FLUORO-3-(4-HYDROXYPHENYL)-2E-PROPENEOATE (3 entities in total)
• 機能のキーワード: cytokine, macrophage, inflammatory response, tautomerase, viral protein
• 由来する生物種: Mus musculus (house mouse)
• 細胞内の位置: Secreted : P34884
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 37692.50

構造登録者

Taylor, A.B.,Johnson Jr., W.H.,Czerwinski, R.M.,Whitman, C.P.,Hackert, M.L. (登録日: 1998-08-12, 公開日: 1999-06-22, 最終更新日: 2024-04-03)

主引用文献

Taylor, A.B.,Johnson Jr., W.H.,Czerwinski, R.M.,Li, H.S.,Hackert, M.L.,Whitman, C.P.
Crystal structure of macrophage migration inhibitory factor complexed with (E)-2-fluoro-p-hydroxycinnamate at 1.8 A resolution: implications for enzymatic catalysis and inhibition.
Biochemistry, 38:7444-7452, 1999

PubMed Abstract: Macrophage migration inhibitory factor (MIF) exhibits dual activities. It acts as an immunoregulatory protein as well as a phenylpyruvate tautomerase. To understand better the relationship between these two activities and to elucidate the structural basis for the enzymatic activity, a crystal structure of a complex between murine MIF and (E)-2-fluoro-p-hydroxycinnamate, a competitive inhibitor of the tautomerase activity, has been determined to 1.8 A resolution. The structure is nearly superimposable on that of the free protein indicating that the presence of the inhibitor does not result in any major structural changes. The inhibitor also confirms the location of the active site in a hydrophobic cavity containing the amino-terminal proline. Within this cavity, the inhibitor interacts with residues from adjacent subunits. At the back of the cavity, the side-chain carbonyl oxygen of Asn-97' interacts with the phenolic hydroxyl group of the inhibitor while at the mouth of the cavity the ammonium group of Lys-32 interacts with a carboxylate oxygen. The other carboxylate oxygen of the inhibitor interacts with Pro-1. The hydroxyl group of Tyr-95' interacts weakly with the fluoro group on the inhibitor. The hydrophobic side chains of five active-site residues (Met-2, Ile-64, Met-101, Val-106, and Phe-113) and the phenyl moiety of Tyr-95' are responsible for the binding of the phenyl group. Further insight into the enzymatic activity of MIF was obtained by carrying out kinetic studies using the enol isomers of phenylpyruvate and (p-hydroxyphenyl)pyruvate. The results demonstrate that MIF processes the enol isomers more efficiently than the keto isomers primarily because of a decrease in Km. On the basis of these results, a mechanism is proposed for the MIF-catalyzed tautomerization reaction.

PubMed: 10360941
DOI: 10.1021/bi9904048

実験手法

X-RAY DIFFRACTION (1.8 Å)