2UYD

Crystal structure of the SmHasA mutant H83A

Summary for 2UYD

• Entry DOI: 10.2210/pdb2uyd/pdb
• Related: 1B2V 1DK0 1DKH 1YBJ 2CN4
• Descriptor: HEMOPHORE HASA, PROTOPORPHYRIN IX CONTAINING FE, ZINC ION, ... (5 entities in total)
• Functional Keywords: heme, iron, hemophore, heme binding, iron ligation, metal-binding, heme acquisition system, metal-binding protein, metal binding protein
• Biological source: SERRATIA MARCESCENS
• Total number of polymer chains: 1
• Total formula weight: 20479.42

Authors

Czjzek, M.,Caillet-Saguy, C.,Fournelle, A.,Guigliarelli, B.,Izadi-Pruneyre, N.,Lecroisey, A. (deposition date: 2007-04-04, release date: 2007-12-25, Last modification date: 2023-12-13)

Primary citation

Caillet-Saguy, C.,Turano, P.,Piccioli, M.,Lukat-Rodgers, G.S.,Czjzek, M.,Guigliarelli, B.,Izadi-Pruneyre, N.,Rodgers, K.R.,Delepierre, M.,Lecroisey, A.
Deciphering the Structural Role of Histidine 83 for Heme Binding in Hemophore Hasa.
J.Biol.Chem., 283:5960-, 2008

PubMed Abstract: Heme carrier HasA has a unique type of histidine/tyrosine heme iron ligation in which the iron ion is in a thermally driven two spin states equilibrium. We recently suggested that the H-bonding between Tyr75 and the invariantly conserved residue His83 modulates the strength of the iron-Tyr75 bond. To unravel the role of His83, we characterize the iron ligation and the electronic properties of both wild type and H83A mutant by a variety of spectroscopic techniques. Although His83 in wild type modulates the strength of the Tyr-iron bond, its removal causes detachment of the tyrosine ligand, thus giving rise to a series of pH-dependent equilibria among species with different axial ligation. The five coordinated species detected at physiological pH may represent a possible intermediate of the heme transfer mechanism to the receptor.

PubMed: 18162469
DOI: 10.1074/JBC.M703795200

Experimental method

X-RAY DIFFRACTION (2.7 Å)