6BL5

Head decoration protein from the hyperthermophilic phage P74-26

Summary for 6BL5

• Entry DOI: 10.2210/pdb6bl5/pdb
• Descriptor: Head decoration protein (2 entities in total)
• Functional Keywords: beta-tulip domain, capsid, virion, viral protein
• Biological source: Thermus virus P74-26
• Total number of polymer chains: 1
• Total formula weight: 16245.43

Authors

Stone, N.P.,Hilbert, B.J.,Hidalgo, D.,Halloran, K.T.,Kelch, B.A. (deposition date: 2017-11-09, release date: 2018-02-21, Last modification date: 2024-03-13)

Primary citation

Stone, N.P.,Hilbert, B.J.,Hidalgo, D.,Halloran, K.T.,Lee, J.,Sontheimer, E.J.,Kelch, B.A.
A Hyperthermophilic Phage Decoration Protein Suggests Common Evolutionary Origin with Herpesvirus Triplex Proteins and an Anti-CRISPR Protein.
Structure, 26:936-947.e3, 2018

PubMed Abstract: Virus capsids are protein shells that protect the viral genome from environmental assaults, while maintaining the high internal pressure of the tightly packaged genome. To elucidate how capsids maintain stability under harsh conditions, we investigated the capsid components of the hyperthermophilic phage P74-26. We determined the structure of capsid protein gp87 and show that it has the same fold as decoration proteins in many other phages, despite lacking significant sequence homology. We also find that gp87 is significantly more stable than mesophilic homologs. Our analysis of the gp87 structure reveals that the core "β tulip" domain is conserved in trimeric capsid components across numerous double-stranded DNA viruses, including Herpesviruses. Moreover, this β barrel domain is found in anti-CRISPR protein AcrIIC1, suggesting a mechanism for the evolution of this Cas9 inhibitor. Our work illustrates the principles for increased stability of gp87, and extends the evolutionary reach of the β tulip domain.

PubMed: 29779790
DOI: 10.1016/j.str.2018.04.008

Experimental method

X-RAY DIFFRACTION (1.69 Å)