1ES1

CRYSTAL STRUCTURE OF VAL61HIS MUTANT OF TRYPSIN-SOLUBILIZED FRAGMENT OF CYTOCHROME B5

Replaces:  1QDX

Summary for 1ES1

• Entry DOI: 10.2210/pdb1es1/pdb
• Related: 1EHB
• Descriptor: CYTOCHROME B5, PROTOPORPHYRIN IX CONTAINING FE (3 entities in total)
• Functional Keywords: cytochrome b5; trypsin-cleaved fragment; mutant val61his;crystal structure; structure comparison with the wild type fragment;, 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, J.,Gan, J.-H.,Xia, Z.-X.,Wang, Y.-H.,Wang, W.-H.,Xue, L.-L.,Xie, Y.,Huang, Z.-X. (deposition date: 2000-04-07, release date: 2000-08-09, Last modification date: 2024-02-07)

Primary citation

Wu, J.,Gan, J.H.,Xia, Z.X.,Wang, Y.H.,Wang, W.H.,Xue, L.L.,Xie, Y.,Huang, Z.X.
Crystal structure of recombinant trypsin-solubilized fragment of cytochrome b(5) and the structural comparison with Val61His mutant.
Proteins, 40:249-257, 2000

PubMed Abstract: The crystal structure of the recombinant trypsin-solubilized fragment of the microsomal cytochrome b(5) from bovine liver has been determined at 1.9 A resolution and compared with the reported crystal structure of the lipase-solubilized fragment of the membrane protein cytochrome b(5). The two structures are similar to each other. However, some detailed structural differences are observed: the conformation of the segment Asn16-Ser20 is quite different, some helices around the heme and some segments between the helices are shifted slightly, the heme is rotated about the normal of the mean plane of heme, one of the propionates of the heme exhibits a different conformation. The average coordination distances between the iron and the two nitrogen atoms of the imidazole ligands are the same in the two structures. Most of the structural differences can be attributed to the different intermolecular interactions which result from the crystal packing. The wild-type protein structure is also compared with its Val61His mutant, showing that the heme binding and the main chain conformations are basically identical with each other except for the local area of the mutation site. However, when Val61 is mutated to histidine, the large side chain of His61 is forced to point away from the heme pocket toward the solvent region, disturbing the micro-environment of the heme pocket and influencing the stability and the redox potential of the protein.

PubMed: 10842340
DOI: 10.1002/(SICI)1097-0134(20000801)40:2<249::AID-PROT70>3.0.CO;2-H

Experimental method

X-RAY DIFFRACTION (2.1 Å)