Mechanism of Host Recognition by the Bacteriophage <i>Cystoviridae</i>

<p>The <em>Cystoviridae</em> is a unique family of double stranded RNA bacteriophage that fuses its outer viral membrane with the lipopolysaccharide membrane of its Gram-negative host. In a series of studies, we determined the specifics of <em>Cystoviridae</em> host binding and the requirements of host fusion. The outer membrane vesicles (OMVs) secreted by the host inhibit <em>Cystoviridae</em> infection. We studied the interaction between OMVs and <em>Cystoviridae</em> to observe the host requirements for binding <em>Cystoviridae</em>. We determined that <em>Cystoviridae</em> strains Phi 8 and Phi 12 recognize the core polysaccharide and lipid A of the host lipopolysaccharide (LPS) for binding. The P6 protein of the <em>Cystoviridae</em> spike complex is suggested to allow fusion of the phage to the host cell. We investigated the P6 residues required for host fusion. The P6 residues of Phi 6 and Phi 12 that are required for fusion are predicted to be in alpha helices. We hypothesize that fusion occurs through coil-to-coil interactions. To observe details of the lifecycle of Phi 8 we utilized in situ cryo electron microscopy. Our results indicate the presence of <em>Cystoviridae</em> in different stages of capsid biogenesis. Lastly, we expressed different forms of the envelope forming protein P9 to purify vesicles containing P9. These vesicles have the potential to determine the P3 residues required for host binding.</p>

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Biology

Grantor

The Graduate School and University Center of The City University of New York

Year dc:date.available

2024

Author dc:creator

• Robinson, Charles F, IV

Advisor dc:contributor.advisor

• Reza Khayat

Committee members dc:contributor.committeemember

• Paul Gottlieb
• Ruth Stark
• John Dennehy
• Enrique Rojas

• Virology
• Cystovirus
• Bacteriophage
• Molecular Biology

Repository record dc:identifier

https://academicworks.cuny.edu/gc_etds/5951

OAI identifier oai:identifier

oai:academicworks.cuny.edu:gc_etds-7063