6CL6

Structure of P. aeruginosa R2 pyocin fiber PA0620 comprising C-terminal residues 323-691

Summary for 6CL6

• Entry DOI: 10.2210/pdb6cl6/pdb
• Descriptor: Tail fiber protein, FE (III) ION, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: r-type pyocin, pseudomonas aeruginosa, contractile injection system, receptor-binding protein, viral protein
• Biological source: Pseudomonas aeruginosa
• Total number of polymer chains: 6
• Total formula weight: 240025.49

Authors

Buth, S.A.,Shneider, M.M.,Leiman, P.G. (deposition date: 2018-03-01, release date: 2018-06-27, Last modification date: 2024-04-03)

Primary citation

Buth, S.A.,Shneider, M.M.,Scholl, D.,Leiman, P.G.
Structure and Analysis of R1 and R2 Pyocin Receptor-Binding Fibers.
Viruses, 10:-, 2018

PubMed Abstract: The R-type pyocins are high-molecular weight bacteriocins produced by some strains of to specifically kill other strains of the same species. Structurally, the R-type pyocins are similar to "simple" contractile tails, such as those of phage P2 and Mu. The pyocin recognizes and binds to its target with the help of fibers that emanate from the baseplate structure at one end of the particle. Subsequently, the pyocin contracts its sheath and drives the rigid tube through the host cell envelope. This causes depolarization of the cytoplasmic membrane and cell death. The host cell surface-binding fiber is ~340 Å-long and is attached to the baseplate with its N-terminal domain. Here, we report the crystal structures of C-terminal fragments of the R1 and R2 pyocin fibers that comprise the distal, receptor-binding part of the protein. Both proteins are ~240 Å-long homotrimers in which slender rod-like domains are interspersed with more globular domains-two tandem knob domains in the N-terminal part of the fragment and a lectin-like domain at its C-terminus. The putative substrate binding sites are separated by about 100 Å, suggesting that binding of the fiber to the cell surface causes the fiber to adopt a certain orientation relative to the baseplate and this then triggers sheath contraction.

PubMed: 30110933
DOI: 10.3390/v10080427

Experimental method

X-RAY DIFFRACTION (1.898 Å)