PDBsum entry 4zid

Electron transport

PDB id: 4zid

Contents

Protein chain

80 a.a.

Ligands

HEC

Waters ×29

PDB id:

4zid

Name:

Electron transport

Title:

Dimeric hydrogenobacter thermophilus cytochrome c552 obtained from escherichia coli

Structure:

CytochromE C-552. Chain: a. Fragment: unp residues 19-98. Synonym: cytochrome c552. Engineered: yes

Source:

Hydrogenobacter thermophilus (strain dsm 6534 / iam 12695 / tk-6). Organism_taxid: 608538. Strain: dsm 6534 / iam 12695 / tk-6. Gene: hth_0988, hydth_0984. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.80Å R-factor: 0.169 R-free: 0.204

Authors:

Y.Hayashi,M.Yamanaka,S.Nagao,H.Komori,Y.Higuchi,S.Hirota

Key ref:

Y.Hayashi et al. (2016). Domain swapping oligomerization of thermostable c-type cytochrome in E. coli cells. Sci Rep, 6, 19334. PubMed id: 26838805 DOI: 10.1038/srep19334

Date:

28-Apr-15 Release date: 10-Feb-16

Protein chain

P15452  (CY552_HYDTT) -  Cytochrome c-552 from Hydrogenobacter thermophilus (strain DSM 6534 / IAM 12695 / TK-6)

Seq: 98 a.a.

Struc: 80 a.a.

DOI no: 10.1038/srep19334

Sci Rep 6:19334 (2016)

PubMed id: 26838805

Domain swapping oligomerization of thermostable c-type cytochrome in E. coli cells.

Y.Hayashi, M.Yamanaka, S.Nagao, H.Komori, Y.Higuchi, S.Hirota.

ABSTRACT

Knowledge on domain swapping in vitro is increasing, but domain swapping may not occur regularly in vivo, and its information in cells is limited. Herein, we show that domain-swapped oligomers of a thermostable c-type cytochrome, Hydrogenobacter thermophilus cyt c552, are formed in E. coli which expresses cyt c552. The region containing the N-terminal α-helix and heme was domain-swapped between protomers in the dimer formed in E. coli. The amount of cyt c552 oligomers increased in E. coli as the cyt c552 concentration was increased, whereas that of high-order oligomers decreased in the order of decrease in protein stability, indicating that domain swapping decreases in cells when the protein stability decreases. Apo cyt c552 was detected in the cyt c552 oligomer formed in E. coli, but not in that of the A5F/M11V/Y32F/Y41E/I76V mutant. The cyt c552 oligomer containing its apo protein may form at the periplasm, since the apo protein detected by mass measurements did not contain the signal peptide. These results show that domain-swapped cyt c552 oligomers were formed in E. coli, owing to the stability of the transient oligomer containing the apo protein before heme attachment. This is an indication that exceedingly stable proteins may have disadvantages forming domain-swapped oligomers in cells.