5HOK

MamB-CTD mutant - D247A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.200 

Starting Model: experimental
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wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The dual role of MamB in magnetosome membrane assembly and magnetite biomineralization.

Uebe, R.Keren-Khadmy, N.Zeytuni, N.Katzmann, E.Navon, Y.Davidov, G.Bitton, R.Plitzko, J.M.Schuler, D.Zarivach, R.

(2018) Mol Microbiol 107: 542-557

  • DOI: https://doi.org/10.1111/mmi.13899
  • Primary Citation of Related Structures:  
    5HO1, 5HO3, 5HO5, 5HOK

  • PubMed Abstract: 

    Magnetospirillum gryphiswaldense MSR-1 synthesizes membrane-enclosed magnetite (Fe 3 O 4 ) nanoparticles, magnetosomes, for magnetotaxis. Formation of these organelles involves a complex process comprising key steps which are governed by specific magnetosome-associated proteins. MamB, a cation diffusion facilitator (CDF) family member has been implicated in magnetosome-directed iron transport. However, deletion mutagenesis studies revealed that MamB is essential for the formation of magnetosome membrane vesicles, but its precise role remains elusive. In this study, we employed a multi-disciplinary approach to define the role of MamB during magnetosome formation. Using site-directed mutagenesis complemented by structural analyses, fluorescence microscopy and cryo-electron tomography, we show that MamB is most likely an active magnetosome-directed transporter serving two distinct, yet essential functions. First, MamB initiates magnetosome vesicle formation in a transport-independent process, probably by serving as a landmark protein. Second, MamB transport activity is required for magnetite nucleation. Furthermore, by determining the crystal structure of the MamB cytosolic C-terminal domain, we also provide mechanistic insight into transport regulation. Additionally, we present evidence that magnetosome vesicle growth and chain formation are independent of magnetite nucleation and magnetic interactions respectively. Together, our data provide novel insight into the role of the key bifunctional magnetosome protein MamB, and the early steps of magnetosome formation.


  • Organizational Affiliation

    Department of Microbiology, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Magnetosome protein MamB
A, B, C, D
85Magnetospira sp. QH-2Mutation(s): 1 
Gene Names: mamBMGMAQ_1061
UniProt
Find proteins for W6KHH6 (Magnetospira sp. (strain QH-2))
Explore W6KHH6 
Go to UniProtKB:  W6KHH6
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupW6KHH6
Sequence Annotations
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download Ideal Coordinates CCD File 
E [auth B]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.70 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.198 
  • R-Value Observed: 0.200 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 37.239α = 90
b = 96.338β = 90
c = 96.724γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
Aimlessdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Ministry of Science, Technology and SpaceIsrael--

Revision History  (Full details and data files)

  • Version 1.0: 2017-02-01
    Type: Initial release
  • Version 1.1: 2018-02-14
    Changes: Data collection, Database references
  • Version 1.2: 2024-01-10
    Changes: Data collection, Database references, Derived calculations, Refinement description