Macromolecule Content

• Total Structure Weight: 6.84 kDa 
• Atom Count: 482 
• Residue Count: 61 
• Unique protein chains: 1

1RZS

Solution structure of P22 Cro

• DOI: 10.2210/pdb1RZS/pdb
• BMRB: 6185

• Classification: TRANSCRIPTION
• Organism(s): Salmonella virus P22
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2003-12-28 Released: 2004-06-01 
• Deposition Author(s): Newlove, T., Konieczka, J.H., Cordes, M.H.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 30 
• Conformers Submitted: 21 
• Selection Criteria: agreement with distance and angle restraints; two structures were also eliminated due to high energy 

Literature

Secondary structure switching in Cro protein evolution.

Newlove, T., Konieczka, J.H., Cordes, M.H.

(2004) Structure 12: 569-581

• PubMed: 15062080 
• DOI: 10.1016/j.str.2004.02.024
• Primary Citation of Related Structures:  
  1RZS


• PubMed Abstract: 
  

We report the solution structure of the Cro protein from bacteriophage P22. Comparisons of its sequence and structure to those of lambda Cro strongly suggest an alpha-to-beta secondary structure switching event during Cro evolution. The folds of P22 Cro and lambda Cro share a three alpha helix fragment comprising the N-terminal half of the domain. However, P22 Cro's C terminus folds as two helices, while lambda Cro's folds as a beta hairpin. The all-alpha fold found for P22 Cro appears to be ancestral, since it also occurs in cI proteins, which are anciently duplicated paralogues of Cro. PSI-BLAST and transitive homology analyses strongly suggest that the sequences of P22 Cro and lambda Cro are globally homologous despite encoding different folds. The alpha+beta fold of lambda Cro therefore likely evolved from its all-alpha ancestor by homologous secondary structure switching, rather than by nonhomologous replacement of both sequence and structure.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85701 USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Regulatory protein cro	A	61	Salmonella virus P22	Mutation(s): 0  Gene Names: cro
Find proteins for P09964 (Salmonella phage P22) Explore P09964  Go to UniProtKB:  P09964

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 30 
• Conformers Submitted: 21 
• Selection Criteria: agreement with distance and angle restraints; two structures were also eliminated due to high energy 
• OLDERADO: 1RZS Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-12-28 
• Released Date: 2004-06-01 
Deposition Author(s): Newlove, T., Konieczka, J.H., Cordes, M.H.

Revision History 

• Version 1.0: 2004-06-01
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance