2BM6

The Structure of MfpA (Rv3361c, C2221 Crystal form). The Pentapeptide Repeat Protein from Mycobacterium tuberculosis Folds as A Right- handed Quadrilateral Beta-helix.

• PDB DOI: https://doi.org/10.2210/pdb2BM6/pdb

• Classification: PENTAPEPTIDE REPEAT PROTEIN
• Organism(s): Mycobacterium tuberculosis H37Rv
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2005-03-09 Released: 2005-06-07 
• Deposition Author(s): Hegde, S.S., Vetting, M.W., Roderick, S.L., Mitchenall, L.A., Maxwell, A., Takiff, H.E., Blanchard, J.S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.256 
• R-Value Work: 0.197 
• R-Value Observed: 0.197 

Starting Model: experimental

Literature

A Fluroquinolone Resistance Protein from Mycobacterium Tuberculosis that Mimics DNA

Hegde, S.S., Vetting, M.W., Roderick, S.L., Mitchenall, L.A., Maxwell, A., Takiff, H.E., Blanchard, J.S.

(2005) Science 308: 1480

• PubMed: 15933203 
• DOI: https://doi.org/10.1126/science.1110699
• Primary Citation of Related Structures:  
  2BM4, 2BM5, 2BM6, 2BM7


• PubMed Abstract: 
  

  Fluoroquinolones are gaining increasing importance in the treatment of tuberculosis. The expression of MfpA, a member of the pentapeptide repeat family of proteins from Mycobacterium tuberculosis, causes resistance to ciprofloxacin and sparfloxacin. This protein binds to DNA gyrase and inhibits its activity. Its three-dimensional structure reveals a fold, which we have named the right-handed quadrilateral beta helix, that exhibits size, shape, and electrostatic similarity to B-form DNA. This represents a form of DNA mimicry and explains both its inhibitory effect on DNA gyrase and fluoroquinolone resistance resulting from the protein's expression in vivo.

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Organizational Affiliation: 

Department of Biochemistry, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 21.12 kDa 
• Atom Count: 1,452 
• Modelled Residue Count: 179 
• Deposited Residue Count: 186 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PENTAPEPTIDE REPEAT FAMILY PROTEIN	A	186	Mycobacterium tuberculosis H37Rv	Mutation(s): 0
UniProt
Find proteins for O50390 (Mycobacterium tuberculosis (strain CDC 1551 / Oshkosh)) Explore O50390  Go to UniProtKB:  O50390

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CS	B [auth A], C [auth A], D [auth A], E [auth A], F [auth A], G [auth A]	CESIUM ION Cs NCMHKCKGHRPLCM-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.256 
• R-Value Work: 0.197 
• R-Value Observed: 0.197 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 33.393	α = 90
b = 48.573	β = 90
c = 188.367	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2005-06-07 
Deposition Author(s): Hegde, S.S., Vetting, M.W., Roderick, S.L., Mitchenall, L.A., Maxwell, A., Takiff, H.E., Blanchard, J.S.

Revision History  

• Version 1.0: 2005-06-07
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-05-01
  Changes: Data collection, Database references, Derived calculations, Other, Refinement description