Origin and function of the two major tail proteins of bacteriophage SPP1

Mol Microbiol. 2008 Nov;70(3):557-69. doi: 10.1111/j.1365-2958.2008.06435.x. Epub 2008 Sep 10.


The majority of bacteriophages have a long non-contractile tail (Siphoviridae) that serves as a conduit for viral DNA traffic from the phage capsid to the host cell at the beginning of infection. The 160-nm-long tail tube of Bacillus subtilis bacteriophage SPP1 is shown to be composed of two major tail proteins (MTPs), gp17.1 and gp17.1*, at a ratio of about 3:1. They share a common amino-terminus, but the latter species has approximately 10 kDa more than gp17.1. A CCC.UAA sequence with overlapping proline codons at the 3' end of gene 17.1 drives a programmed translational frameshift to another open reading frame. The recoding event generates gp17.1*. Phages carrying exclusively gp17.1 or gp17.1* are viable, but tails are structurally distinct. gp17.1 and the carboxyl-terminus of gp17.1* have a distinct evolutionary history correlating with different functions: the polypeptide sequence identical in the two proteins is responsible for assembly of the tail tube while the additional module of gp17.1* shields the structure exterior exposed to the environment. The carboxyl-terminal extension is an elaboration present in some tailed bacteriophages. Different extensions were found to combine in a mosaic fashion with the MTP essential module in a subset of Siphoviridae genomes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus Phages / genetics*
  • Bacillus Phages / physiology
  • Bacillus subtilis / virology
  • DNA, Viral / genetics
  • Escherichia coli / genetics
  • Evolution, Molecular
  • Frameshifting, Ribosomal*
  • Genes, Viral
  • Genome, Viral
  • Mutagenesis, Site-Directed
  • Mutation
  • Nucleic Acid Conformation
  • Open Reading Frames
  • Plasmids
  • Sequence Homology, Amino Acid
  • Viral Tail Proteins / genetics*
  • Virus Replication / genetics


  • DNA, Viral
  • Viral Tail Proteins