1J0Q

Solution Structure of Oxidized Bovine Microsomal Cytochrome b5 mutant V61H

Summary for 1J0Q

• Entry DOI: 10.2210/pdb1j0q/pdb
• Descriptor: cytochrome b5, PROTOPORPHYRIN IX CONTAINING FE (2 entities in total)
• Functional Keywords: helix, beta, electron transport
• Biological source: Bos taurus (cattle)
• Cellular location: Endoplasmic reticulum membrane; Single-pass membrane protein; Cytoplasmic side: P00171
• Total number of polymer chains: 1
• Total formula weight: 10130.88

Authors

Wu, H.,Huang, Z.,Cao, C.,Zhang, Q.,Wang, Y.-H.,Ma, J.-B.,Xue, L.-L. (deposition date: 2002-11-20, release date: 2003-08-12, Last modification date: 2023-12-27)

Primary citation

Cao, C.,Zhang, Q.,Xue, L.-L.,Ma, J.,Wang, Y.-H.,Wu, H.,Huang, Z.-X.
The solution structure of the oxidized bovine microsomal cytochrome b5 mutant V61H
Biochem.Biophys.Res.Commun., 307:600-609, 2003

PubMed Abstract: Using 1488 NOE constraints, 19 stereo-specific assignments, 13 pairs of H-bond constraints, and 140 pseudo-contact shift constraints, a family of 35 structures of bovine microsomal cytochrome b(5) mutant V61H has been obtained through the program PSEUDYANA. The family has been further refined by restrained energy minimization to give a family of final structures. The RMSD values of final structures with respect to the average structure are 0.45+/-0.11 and 0.96+/-0.10A for backbone and heavy atoms, respectively. The final Deltachi(ax) and Deltachi(rh) values are 2.34 x 10(-32) and -0.67 x 10(-32)m(3), respectively. The comparisons between the solution structures of mutant V61H and WT cytochrome b(5), and X-ray structure of the mutant V61H show that the global folding of the molecule in solution is unchanged and the side-chain of His61 deviates from the heme pocket and extends into the solvent like in its crystal structure. However, the helices around the heme pocket undergo outward global displacement while their local conformations are well maintained. Meanwhile, the heme ring shows a little off the heme pocket, which accounts for the lower stability of the mutant. Additionally, the axial ligand rings counterclockwise rotate around His39 N-Fe axis due to the mutation, which is confirmed by variation of the hyperfine shifts of the heme protons of V61H compared to those of WT cytochrome b(5).

PubMed: 12893266
DOI: 10.1016/S0006-291X(03)01225-7

Experimental method

SOLUTION NMR