Eligible Student Poster 49th Lorne Conference on Protein Structure and Function 2024

Unravelling the structural complexity of enveloped bacteriophages and exploring the role of phage proteins in the infection cycle (#130)

Somavally Dalvi 1 , Chani Rakov 2 , Matthew Johnson 1 , Qinyu Xia 1 , Sigal Ben-Yehuda 2 , Debnath Ghosal 1
  1. University of Melbourne, Melbourne, VIC, Australia
  2. Department of Microbiology and Molecular genetics, IMRIC, The Hebrew University-Hadassah Medical school, The Hebrew university of Jerusalem, Jerusalem, Israel

Bacteriophages are the most common biological entities and found in every biosphere. Bacteriophages can be classified into eleven families based on the nucleic acid composition, capsid symmetry, and presence or absence of a membrane or envelope. Unlike mammalian viruses, relatively few bacteriophages have an internal or exterior membrane1. Despite the fact that membrane-containing phages have been discovered for over 50 years, the structural details of the majority of the proteins still remains a mystery.  How these phage proteins aid in infection cycle inside the host cell, still remains enigmatic.

In this study, we elucidated the structural intricacies of membrane-containing phages at unprecedented resolution by combining complementary methods, including biochemistry, fluorescence microscopy, and cryo-electron tomography (Cryo-ET). By employing cryo-ET and sub-tomogram averaging, we unveiled the structural details of phage spike protein, nucleocapsid and the packaging enzyme. This study offers valuable insights into the functions of phage proteins during the infection cycle within the host cell. 

  1. Dion, M. B., Oechslin, F., Moineau, S. (2020). Phage Diversity, Genomics and Phylogeny. Nat. Rev. Microbiol. 18, 125–138. doi: 10.1038/s41579-019-0311-5