Atomic structure of Mycobacterium tuberculosis DppA

Experimental Data Snapshot

  • Resolution: 1.25 Å
  • R-Value Free: 0.188 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.168 

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This is version 1.3 of the entry. See complete history


Heme and hemoglobin utilization by Mycobacterium tuberculosis.

Mitra, A.Ko, Y.H.Cingolani, G.Niederweis, M.

(2019) Nat Commun 10: 4260-4260

  • DOI: https://doi.org/10.1038/s41467-019-12109-5
  • Primary Citation of Related Structures:  
    6E3D, 6E4D

  • PubMed Abstract: 

    Iron is essential for growth of Mycobacterium tuberculosis (Mtb), but most iron in the human body is stored in heme within hemoglobin. Here, we demonstrate that the substrate-binding protein DppA of the inner membrane Dpp transporter is required for heme and hemoglobin utilization by Mtb. The 1.27 Å crystal structure of DppA shows a tetrapeptide bound in the protein core and a large solvent-exposed crevice for heme binding. Mutation of arginine 179 in this cleft eliminates heme binding to DppA and prevents heme utilization by Mtb. The outer membrane proteins PPE36 and PPE62 are also required for heme and hemoglobin utilization, indicating that these pathways converge at the cell surface of Mtb. Albumin, the most abundant blood protein, binds heme specifically and bypasses the requirements for PPE36, PPE62 and Dpp. Thus, our study reveals albumin-dependent and -independent heme uptake pathways, highlighting the importance of iron acquisition from heme for Mtb.

  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233S. 10th Street, Philadelphia, PA, 19107, USA. Gino.Cingolani@jefferson.edu.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Periplasmic dipeptide-binding lipoprotein DPPA510Mycobacterium tuberculosisMutation(s): 1 
Gene Names: dppAERS007741_01322ERS023446_02924
Find proteins for I6X811 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore I6X811 
Go to UniProtKB:  I6X811
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupI6X811
Sequence Annotations
  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
VAL-VAL-VAL-ALAB [auth F]4Escherichia coliMutation(s): 0 
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.25 Å
  • R-Value Free: 0.188 
  • R-Value Work: 0.168 
  • R-Value Observed: 0.168 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 52.62α = 90
b = 68.951β = 106.34
c = 62.108γ = 90
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

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Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesP30CA56036
National Institutes of Health/Office of the DirectorUnited StatesS10OD017987

Revision History  (Full details and data files)

  • Version 1.0: 2019-09-11
    Type: Initial release
  • Version 1.1: 2019-11-06
    Changes: Data collection, Database references
  • Version 1.2: 2019-12-04
    Changes: Author supporting evidence
  • Version 1.3: 2023-10-11
    Changes: Data collection, Database references, Refinement description