2KCA

GP16

Summary for 2KCA

• Entry DOI: 10.2210/pdb2kca/pdb
• NMR Information: BMRB: 16068
• Descriptor: Bacteriophage SPP1 complete nucleotide sequence (1 entity in total)
• Functional Keywords: beta-barrel, viral protein
• Biological source: Bacillus phage SPP1 (Bacteriophage SPP1)
• Total number of polymer chains: 1
• Total formula weight: 12615.07

Authors

Gallopin, M.,Gilquin, B.,Zinn-Justin, S. (deposition date: 2008-12-18, release date: 2009-06-02, Last modification date: 2024-05-22)

Primary citation

Lhuillier, S.,Gallopin, M.,Gilquin, B.,Brasiles, S.,Lancelot, N.,Letellier, G.,Gilles, M.,Dethan, G.,Orlova, E.V.,Couprie, J.,Tavares, P.,Zinn-Justin, S.
Structure of bacteriophage SPP1 head-to-tail connection reveals mechanism for viral DNA gating.
Proc.Natl.Acad.Sci.USA, 106:8507-8512, 2009

PubMed Abstract: In many bacterial viruses and in certain animal viruses, the double-stranded DNA genome enters and exits the capsid through a portal gatekeeper. We report a pseudoatomic structure of a complete portal system. The bacteriophage SPP1 gatekeeper is composed of dodecamers of the portal protein gp6, the adaptor gp15, and the stopper gp16. The solution structures of gp15 and gp16 were determined by NMR. They were then docked together with the X-ray structure of gp6 into the electron density of the approximately 1-MDa SPP1 portal complex purified from DNA-filled capsids. The resulting structure reveals that gatekeeper assembly is accompanied by a large rearrangement of the gp15 structure and by folding of a flexible loop of gp16 to form an intersubunit parallel beta-sheet that closes the portal channel. This stopper system prevents release of packaged DNA. Disulfide cross-linking between beta-strands of the stopper blocks the key conformational changes that control genome ejection from the virus at the beginning of host infection.

PubMed: 19433794
DOI: 10.1073/pnas.0812407106

Experimental method

SOLUTION NMR