2J8I

Structure of NP275, a pentapeptide repeat protein from Nostoc punctiforme

• PDB DOI: https://doi.org/10.2210/pdb2J8I/pdb

• Classification: TOXIN
• Organism(s): Nostoc punctiforme
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2006-10-25 Released: 2006-12-07 
• Deposition Author(s): Vetting, M.W., Hegde, S.S., Hazleton, K.Z., Blanchard, J.S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.256 
• R-Value Work: 0.188 
• R-Value Observed: 0.191 

Literature

Structural Characterization of the Fusion of Two Pentapeptide Repeat Proteins, Np275 and Np276, from Nostoc Punctiforme: Resurrection of an Ancestral Protein.

Vetting, M.W., Hegde, S.S., Hazleton, K.Z., Blanchard, J.S.

(2007) Protein Sci 16: 755

• PubMed: 17384236 
• DOI: https://doi.org/10.1110/ps.062637707
• Primary Citation of Related Structures:  
  2J8I, 2J8K


• PubMed Abstract: 
  

  The Nostoc punctiforme genes Np275 and Np276 are two adjacently encoded proteins of 98 and 75 amino acids in length and exhibit sequences composed of tandem pentapeptide repeats. The structures of Np275 and a fusion of Np275 and Np276 were determined to 2.1 and 1.5 A, respectively. The two Nostoc proteins fold as highly symmetric right-handed quadrilateral beta-helices similar to the mycobacterial protein MfpA implicated in fluoroquinolone resistance and DNA gyrase inhibition. The sequence composition of the intervening coding region and the ability to express a fused protein by removing the stop codon for Np275 suggests Np275 and Np276 were recently part of a larger ancestral pentapeptide repeat protein.

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Organizational Affiliation: 

Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 25.03 kDa 
• Atom Count: 1,749 
• Modelled Residue Count: 222 
• Deposited Residue Count: 236 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
NP275	A, B	118	Nostoc punctiforme	Mutation(s): 0

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CL	C [auth B]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.256 
• R-Value Work: 0.188 
• R-Value Observed: 0.191 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 29.181	α = 90
b = 62.558	β = 90
c = 100.549	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
CCP4	data scaling
MOLREP	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2006-12-07 
Deposition Author(s): Vetting, M.W., Hegde, S.S., Hazleton, K.Z., Blanchard, J.S.

Revision History  

• Version 1.0: 2006-12-07
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance
• Version 1.2: 2023-12-13
  Changes: Data collection, Database references, Other, Refinement description