Biological Assembly 1  

 3D View: Structure | Electron Density

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 22.68 kDa 
• Atom Count: 1610 
• Modelled Residue Count: 186 
• Deposited Residue Count: 205 
• Unique protein chains: 1

1RYB

Crystal Structure of the Chloroplast Group II Intron Splicing Factor CRS2

• DOI: 10.2210/pdb1RYB/pdb

• Classification: HYDROLASE
• Organism(s): Zea mays
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2003-12-21 Released: 2003-12-30 
• Deposition Author(s): Ostheimer, G.J., Barkan, A., Matthews, B.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free: 0.246 
• R-Value Work: 0.173 
• R-Value Observed: 0.176 

Literature

Structural analysis of the group II intron splicing factor CRS2 yields insights into its protein and RNA interaction surfaces

Ostheimer, G.J., Hadjivasiliou, H., Kloer, D.P., Barkan, A., Matthews, B.W.

(2005) J Mol Biol 345: 51-68

• PubMed: 15567410 
• DOI: 10.1016/j.jmb.2004.10.032
• Primary Citation of Related Structures:  
  1RYN, 1RYM, 1RYB


• PubMed Abstract: 
  

Chloroplast RNA splicing 2 (CRS2) is a nuclear-encoded protein required for the splicing of nine group II introns in maize chloroplasts. CRS2 functions in the context of splicing complexes that include one of two CRS2-associated factors (CAF1 and CAF2). The CRS2-CAF1 and CRS2-CAF2 complexes are required for the splicing of different subsets of CRS2-dependent introns, and they bind tightly and specifically to their genetically defined intron targets in vivo. The CRS2 amino acid sequence is closely related to those of bacterial peptidyl-tRNA hydrolases (PTHs). To identify the structural differences between CRS2 and bacterial PTHs responsible for CRS2's gains of CAF binding and intron splicing functions, we determined the structure of CRS2 by X-ray crystallography. The fold of CRS2 is the same as that of Escherichia coli PTH, but CRS2 has two surfaces that differ from the corresponding surfaces in PTH. One of these is more hydrophobic in CRS2 than in PTH. Site-directed mutagenesis of this surface blocked CRS2-CAF complex formation, indicating that it is the CAF binding site. The CRS2 surface corresponding to the putative tRNA binding face of PTH is considerably more basic than in PTH, suggesting that CRS2 interacts with group II intron substrates via this surface. Both the sequence and the structural context of the amino acid residues essential for peptidyl-tRNA hydrolase activity are conserved in CRS2, yet expression of CRS2 is incapable of rescuing a pth(ts)E.coli strain.

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Organizational Affiliation: 

Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CRS2	A	205	Zea mays	Mutation(s): 0  Gene Names: CRS2 EC: 3.1.1.29
Find proteins for Q9M5P4 (Zea mays) Explore Q9M5P4  Go to UniProtKB:  Q9M5P4

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free: 0.246 
• R-Value Work: 0.173 
• R-Value Observed: 0.176 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 36.375	α = 90
b = 62.644	β = 90
c = 78.235	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
EPMR	phasing
TNT	refinement
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-12-21 
• Released Date: 2003-12-30 
Deposition Author(s): Ostheimer, G.J., Barkan, A., Matthews, B.W.

Revision History  

• Version 1.0: 2003-12-30
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance