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Self-assembly of Complex Two-dimensional Shapes from Single-stranded DNA Tiles
Published on: May 8, 2015
A conserved spiral structure for highly diverged phage tail assembly chaperones
Lisa G Pell1, Nichole Cumby, Teresa E Clark
1Department of Molecular Genetics and Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada M5S 3E1.
Journal of Molecular Biology
|April 2, 2013
Summary
Tail assembly chaperones (TACs) are crucial for phage morphogenesis. This study reveals conserved ring structures in TACs, despite sequence divergence, highlighting spiral formation
Area of Science:
- Structural biology
- Molecular biology
- Virology
Background:
- Tail assembly chaperones (TACs) are essential proteins for the morphogenesis of long-tailed bacteriophages.
- Understanding TAC structure-function relationships is key to phage biology.
Purpose of the Study:
- To determine the crystal structure of gp13, the TAC from phage HK97.
- To compare the structure of gp13 with other known and putative TACs.
- To investigate the evolutionary significance of conserved quaternary structures in TACs.
Main Methods:
- X-ray crystallography to determine the three-dimensional structure of gp13.
- Comparative structural analysis of gp13 with homologous proteins.
- Functional assays to support the biological relevance of observed structures.
Main Results:
- The crystal structure of gp13 reveals a ring-like quaternary structure.
- gp13 shares similar ring dimensions with TACs from Lactococcus phage p2 and unannotated Bacillus proteins.
- Despite conserved quaternary structure, interprotomer interactions differ significantly among these TACs.
- Functional data supports the biological relevance of spiral formations in TACs.
Conclusions:
- Conserved quaternary structure, specifically spiral formation, is a key evolutionary driver for tail assembly chaperones.
- Diverged protein sequences and oligomerization mechanisms can converge on similar overall structures.
- This study provides insights into the evolution of protein structure and function in bacteriophages.
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