PMID:21898653
| Citation |
Zhang, Y, Fu, J, Chee, SY, Ang, EX and Orner, BP (2011) Rational disruption of the oligomerization of the mini-ferritin E. coli DPS through protein-protein interface mutation. Protein Sci. 20:1907-17 |
|---|---|
| Abstract |
DNA-binding protein from starved cells (DPS), a mini-ferritin capable of self-assembling into a 12-meric nano-cage, was chosen as the basis for an alanine-shaving mutagenesis study to investigate the importance of key amino acid residues, located at symmetry-related protein-protein interfaces, in controlling protein stability and self-assembly. Nine mutants were designed through simple inspection, synthesized, and subjected to transmission electron microscopy, circular dichroism, size exclusion chromatography, and "virtual alanine scanning" computational analysis. The data indicate that many of these residues may be hot spot residues. Most remarkably, two residues, R83 and R133, were observed to shift the oligomerization state to ~50% dimer. Based on the hypothesis that these two residues constitute a "hot strip," located at the ferritin-like threefold axis, the double mutant was generated which completely shuts down detectable formation of 12-mer in solution, favoring a cooperatively folded dimer. The fact that this effect logically builds upon the single mutants emphasizes that complex self-assembly has the potential to be manipulated rationally. This study should have an impact on the fundamental understanding of the assembly of DPS protein cages specifically and protein quaternary structure in general. In addition, as there is much interest in applying these and similar systems to the templation of nano-materials and drug delivery, the ability to control this ferritin's oligomerization state and stability could prove especially valuable. |
| Links |
PubMed PMC3267954 Online version:10.1002/pro.731 |
| Keywords |
Amino Acid Substitution; Amino Acids; Bacterial Outer Membrane Proteins/chemistry; Bacterial Outer Membrane Proteins/genetics; Bacterial Outer Membrane Proteins/metabolism; Crystallography, X-Ray; Escherichia coli/chemistry; Escherichia coli/genetics; Escherichia coli/metabolism; Escherichia coli Proteins/chemistry; Escherichia coli Proteins/genetics; Escherichia coli Proteins/metabolism; Ferritins/chemistry; Ferritins/metabolism; Models, Molecular; Mutagenesis; Protein Biosynthesis; Protein Conformation; Protein Folding; Protein Interaction Domains and Motifs/genetics; Protein Stability; Protein Structure, Quaternary; Protein Structure, Secondary; Sequence Alignment |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
See also
References
See Help:References for how to manage references in EcoliWiki.