Structure solution of C-reactive proteins: molecular replacement with a twist
A K Shrive1, D Holden, D A Myles
1Department of Physics, Keele University, Staffordshire, England.
Acta Crystallographica. Section D, Biological Crystallography
|November 1, 1996
Summary
Researchers determined the pentameric structure of C-reactive protein (CRP) using modified molecular replacement. This method, applicable to other protein assemblies, reveals how similar protein structures can form different complexes.
Area of Science:
- Structural biology
- Biochemistry
- Molecular biology
Background:
- C-reactive protein (CRP) is a key inflammatory marker.
- Determining the pentameric structure of CRP is crucial for understanding its function.
- Existing methods struggled to resolve CRP's pentameric assembly.
Purpose of the Study:
- To derive the pentameric structure of C-reactive protein (CRP).
- To develop a generally applicable molecular replacement method for multimeric protein assemblies.
- To investigate how sequence homology influences protein assembly.
Main Methods:
- Utilized a combination of automated and manual molecular replacement techniques.
- Modified the structure of human serum amyloid P component (hSAP) to solve the CRP structure.
- Analyzed protomer rotation and assembly in relation to pentameric symmetry.
Main Results:
- Successfully derived the pentameric structure model of CRP.
- Demonstrated that highly homologous protein protomers can assemble differently while maintaining oligomeric symmetry.
- The modified hSAP structure provided a solution for CRP, not CRP's own structure.
Conclusions:
- The study presents a robust method for solving multimeric protein structures.
- Protein structure does not strictly dictate assembly, even with high sequence homology.
- The derived CRP model aids in solving other related protein structures.
