7LB8

Structure of a ferrichrome importer FhuCDB from E. coli


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.40 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Cryo-EM reveals unique structural features of the FhuCDB Escherichia coli ferrichrome importer.

Hu, W.Zheng, H.

(2021) Commun Biol 4: 1383-1383

  • DOI: 10.1038/s42003-021-02916-2
  • Primary Citation of Related Structures:  
    7LB8

  • PubMed Abstract: 
  • As one of the most elegant biological processes developed in bacteria, the siderophore-mediated iron uptake demands the action of specific ATP-binding cassette (ABC) importers. Although extensive studies have been done on various ABC importers, the molecular basis of these iron-chelated-siderophore importers are still not fully understood ...

    As one of the most elegant biological processes developed in bacteria, the siderophore-mediated iron uptake demands the action of specific ATP-binding cassette (ABC) importers. Although extensive studies have been done on various ABC importers, the molecular basis of these iron-chelated-siderophore importers are still not fully understood. Here, we report the structure of a ferrichrome importer FhuCDB from Escherichia coli at 3.4 Å resolution determined by cryo electron microscopy. The structure revealed a monomeric membrane subunit of FhuB with a substrate translocation pathway in the middle. In the pathway, there were unique arrangements of residues, especially layers of methionines. Important residues found in the structure were interrogated by mutagenesis and functional studies. Surprisingly, the importer's ATPase activity was decreased upon FhuD binding, which deviated from the current understanding about bacterial ABC importers. In summary, to the best of our knowledge, these studies not only reveal a new structural twist in the type II ABC importer subfamily, but also provide biological insights in the transport of iron-chelated siderophores.


    Organizational Affiliation

    Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, School of Medicine, Aurora, USA. hongjin.zheng@cuanschutz.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Iron(3+)-hydroxamate import system permease protein FhuBA [auth B]668Escherichia coli K-12Mutation(s): 0 
Gene Names: fhuBb0153JW0149
Membrane Entity: Yes 
UniProt
Find proteins for P06972 (Escherichia coli (strain K12))
Explore P06972 
Go to UniProtKB:  P06972
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP06972
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Iron(3+)-hydroxamate-binding protein FhuDB [auth D]296Escherichia coli K-12Mutation(s): 0 
Gene Names: fhuDb0152JW0148
Membrane Entity: Yes 
UniProt
Find proteins for P07822 (Escherichia coli (strain K12))
Explore P07822 
Go to UniProtKB:  P07822
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP07822
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
Iron(3+)-hydroxamate import ATP-binding protein FhuCD [auth C],
C [auth U]
265Escherichia coli K-12Mutation(s): 0 
Gene Names: fhuCb0151JW0147
EC: 7.2.2.16
Membrane Entity: Yes 
UniProt
Find proteins for P07821 (Escherichia coli (strain K12))
Explore P07821 
Go to UniProtKB:  P07821
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP07821
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.40 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM126626
National Institutes of Health/National Institute on Aging (NIH/NIA)United StatesAG064572

Revision History  (Full details and data files)

  • Version 1.0: 2021-11-24
    Type: Initial release
  • Version 1.1: 2022-06-08
    Changes: Database references