2X53

Structure of the phage p2 baseplate in its activated conformation with Sr

Summary for 2X53

• Entry DOI: 10.2210/pdb2x53/pdb
• Related: 2WZP 2X54 2X5A
• EMDB information: 1699
• Descriptor: ORF16, PUTATIVE RECEPTOR BINDING PROTEIN, ORF15, ... (4 entities in total)
• Functional Keywords: baseplate, viral protein
• Biological source: LACTOCOCCUS PHAGE P2 (PHAGE P2); More
• Total number of polymer chains: 27
• Total formula weight: 849424.02

Authors

Sciara, G.,Bebeacua, C.,Bron, P.,Tremblay, D.,Ortiz-Lombardia, M.,Lichiere, J.,van Heel, M.,Campanacci, V.,Moineau, S.,Cambillau, C. (deposition date: 2010-02-05, release date: 2010-02-16, Last modification date: 2023-12-20)

Primary citation

Sciara, G.,Bebeacua, C.,Bron, P.,Tremblay, D.,Ortiz-Lombardia, M.,Lichiere, J.,van Heel, M.,Campanacci, V.,Moineau, S.,Cambillau, C.
Structure of Lactococcal Phage P2 Baseplate and its Mechanism of Activation.
Proc.Natl.Acad.Sci.USA, 107:6852-, 2010

PubMed Abstract: Siphoviridae is the most abundant viral family on earth which infects bacteria as well as archaea. All known siphophages infecting gram+ Lactococcus lactis possess a baseplate at the tip of their tail involved in host recognition and attachment. Here, we report analysis of the p2 phage baseplate structure by X-ray crystallography and electron microscopy and propose a mechanism for the baseplate activation during attachment to the host cell. This approximately 1 MDa, Escherichia coli-expressed baseplate is composed of three protein species, including six trimers of the receptor-binding protein (RBP). RBPs host-recognition domains point upwards, towards the capsid, in agreement with the electron-microscopy map of the free virion. In the presence of Ca(2+), a cation mandatory for infection, the RBPs rotated 200 degrees downwards, presenting their binding sites to the host, and a channel opens at the bottom of the baseplate for DNA passage. These conformational changes reveal a novel siphophage activation and host-recognition mechanism leading ultimately to DNA ejection.

PubMed: 20351260
DOI: 10.1073/PNAS.1000232107

Experimental method

X-RAY DIFFRACTION (3.9 Å)