3EEE

Probing the function of heme distortion in the H-NOX family

Summary for 3EEE

• Entry DOI: 10.2210/pdb3eee/pdb
• Related: 1U4H 1U55 1U56
• Descriptor: Methyl-accepting chemotaxis protein, PROTOPORPHYRIN IX CONTAINING FE, OXYGEN MOLECULE, ... (6 entities in total)
• Functional Keywords: hemoprotein, signaling protein
• Biological source: Thermoanaerobacter tengcongensis
• Total number of polymer chains: 4
• Total formula weight: 91038.90

Authors

Olea Jr, C.,Boon, E.M.,Pellicena, P.,Kuriyan, J.,Marletta, M.A. (deposition date: 2008-09-04, release date: 2008-11-25, Last modification date: 2023-08-30)

Primary citation

Olea, C.,Boon, E.M.,Pellicena, P.,Kuriyan, J.,Marletta, M.A.
Probing the function of heme distortion in the H-NOX family.
Acs Chem.Biol., 3:703-710, 2008

PubMed Abstract: Hemoproteins carry out diverse functions utilizing a wide range of chemical reactivity while employing the same heme prosthetic group. It is clear from high-resolution crystal structures and biochemical studies that protein-bound hemes are not planar and adopt diverse conformations. The crystal structure of an H-NOX domain from Thermoanaerobacter tengcongensis (Tt H-NOX) contains the most distorted heme reported to date. In this study, Tt H-NOX was engineered to adopt a flatter heme by mutating proline 115, a conserved residue in the H-NOX family, to alanine. Decreasing heme distortion in Tt H-NOX increases affinity for oxygen and decreases the reduction potential of the heme iron. Additionally, flattening the heme is associated with significant shifts in the N-terminus of the protein. These results show a clear link between the heme conformation and Tt H-NOX structure and demonstrate that heme distortion is an important determinant for maintaining biochemical properties in H-NOX proteins.

PubMed: 19032091
DOI: 10.1021/cb800185h

Experimental method

X-RAY DIFFRACTION (2.12 Å)