5AQ5

Structure of the Carboxy-Terminal Domain of the Bacteriophage T5 L- Shaped Tail Fibre

Summary for 5AQ5

• Entry DOI: 10.2210/pdb5aq5/pdb
• Descriptor: L-SHAPED TAIL FIBER PROTEIN PB8 (2 entities in total)
• Functional Keywords: viral protein
• Biological source: ESCHERICHIA PHAGE T5
• Total number of polymer chains: 12
• Total formula weight: 413486.53

Authors

Garcia-Doval, C.,Granell, M.,van Raaij, M.J. (deposition date: 2015-09-19, release date: 2015-12-16, Last modification date: 2024-01-10)

Primary citation

Garcia-Doval, C.,Caston, J.R.,Luque, D.,Granell, M.,Otero, J.M.,Llamas-Saiz, A.L.,Renouard, M.,Boulanger, P.,van Raaij, M.J.
Structure of the Receptor-Binding Carboxy-Terminal Domain of the Bacteriophage T5 L-Shaped Tail Fibre with and without Its Intra-Molecular Chaperone.
Viruses, 7:6424-6440, 2015

PubMed Abstract: Bacteriophage T5, a Siphovirus belonging to the order Caudovirales, has a flexible, three-fold symmetric tail, to which three L-shaped fibres are attached. These fibres recognize oligo-mannose units on the bacterial cell surface prior to infection and are composed of homotrimers of the pb1 protein. Pb1 has 1396 amino acids, of which the carboxy-terminal 133 residues form a trimeric intra-molecular chaperone that is auto-proteolyzed after correct folding. The structure of a trimer of residues 970-1263 was determined by single anomalous dispersion phasing using incorporated selenomethionine residues and refined at 2.3 Å resolution using crystals grown from native, methionine-containing, protein. The protein inhibits phage infection by competition. The phage-distal receptor-binding domain resembles a bullet, with the walls formed by partially intertwined beta-sheets, conferring stability to the structure. The fold of the domain is novel and the topology unique to the pb1 structure. A site-directed mutant (Ser1264 to Ala), in which auto-proteolysis is impeded, was also produced, crystallized and its 2.5 Å structure solved by molecular replacement. The additional chaperone domain (residues 1263-1396) consists of a central trimeric alpha-helical coiled-coil flanked by a mixed alpha-beta domain. Three long beta-hairpin tentacles, one from each chaperone monomer, extend into long curved grooves of the bullet-shaped domain. The chaperone-containing mutant did not inhibit infection by competition.

PubMed: 26670244
DOI: 10.3390/v7122946

Experimental method

X-RAY DIFFRACTION (2.3 Å)