Structure and host specificity of Staphylococcus epidermidis bacteriophage Andhra

Sci Adv. 2022 Dec 2;8(48):eade0459. doi: 10.1126/sciadv.ade0459. Epub 2022 Nov 30.

Abstract

Staphylococcus epidermidis is an opportunistic pathogen of the human skin, often associated with infections of implanted medical devices. Staphylococcal picoviruses are a group of strictly lytic, short-tailed bacteriophages with compact genomes that are attractive candidates for therapeutic use. Here, we report the structure of the complete virion of S. epidermidis-infecting phage Andhra, determined using high-resolution cryo-electron microscopy, allowing atomic modeling of 11 capsid and tail proteins. The capsid is a T = 4 icosahedron containing a unique stabilizing capsid lining protein. The tail includes 12 trimers of a unique receptor binding protein (RBP), a lytic protein that also serves to anchor the RBPs to the tail stem, and a hexameric tail knob that acts as a gatekeeper for DNA ejection. Using structure prediction with AlphaFold, we identified the two proteins that comprise the tail tip heterooctamer. Our findings elucidate critical features for virion assembly, host recognition, and penetration.

MeSH terms

  • Capsid
  • Capsid Proteins
  • Cryoelectron Microscopy
  • Host Specificity*
  • Humans
  • Staphylococcus Phages*
  • Staphylococcus epidermidis

Substances

  • Capsid Proteins