PDBsum entry 4lm8

Electron transport

PDB id: 4lm8

Contents

Protein chain

626 a.a.

Ligands

HEC ×10

EDO ×8

ACT

Metals

_CA ×5

Waters ×936

PDB id:

4lm8

Name:

Electron transport

Title:

Crystal structure of the outer membrane decaheme cytochrome mtrc

Structure:

Extracellular iron oxide respiratory system surface decaheme cytochromE C component mtrc. Chain: a. Fragment: mtrc (unp residues 26-671). Engineered: yes

Source:

Shewanella oneidensis. Organism_taxid: 211586. Strain: mr-1. Gene: mtrc, so_1778. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

1.80Å R-factor: 0.168 R-free: 0.203

Authors:

T.A.Clarke,M.J.Edwards

Key ref:

M.J.Edwards et al. (2015). Redox Linked Flavin Sites in Extracellular Decaheme Proteins Involved in Microbe-Mineral Electron Transfer. Sci Rep, 5, 11677. PubMed id: 26126857 DOI: 10.1038/srep11677

Date:

10-Jul-13 Release date: 11-Feb-15

Protein chain

Q8EG34  (Q8EG34_SHEON) -  Extracellular iron oxide respiratory system surface decaheme cytochrome c component MtrC from Shewanella oneidensis (strain ATCC 700550 / JCM 31522 / CIP 106686 / LMG 19005 / NCIMB 14063 / MR-1)

Seq: 671 a.a.

Struc: 626 a.a.

DOI no: 10.1038/srep11677

Sci Rep 5:11677 (2015)

PubMed id: 26126857

Redox Linked Flavin Sites in Extracellular Decaheme Proteins Involved in Microbe-Mineral Electron Transfer.

M.J.Edwards, G.F.White, M.Norman, A.Tome-Fernandez, E.Ainsworth, L.Shi, J.K.Fredrickson, J.M.Zachara, J.N.Butt, D.J.Richardson, T.A.Clarke.

ABSTRACT

Extracellular microbe-mineral electron transfer is a major driving force for the oxidation of organic carbon in many subsurface environments. Extracellular multi-heme cytochromes of the Shewenella genus play a major role in this process but the mechanism of electron exchange at the interface between cytochrome and acceptor is widely debated. The 1.8 Å x-ray crystal structure of the decaheme MtrC revealed a highly conserved CX8C disulfide that, when substituted for AX8A, severely compromised the ability of S. oneidensis to grow under aerobic conditions. Reductive cleavage of the disulfide in the presence of flavin mononucleotide (FMN) resulted in the reversible formation of a stable flavocytochrome. Similar results were also observed with other decaheme cytochromes, OmcA, MtrF and UndA. The data suggest that these decaheme cytochromes can transition between highly reactive flavocytochromes or less reactive cytochromes, and that this transition is controlled by a redox active disulfide that responds to the presence of oxygen.