"Portals and DNA packaging in tailed bacteriophages and herpesviruses"
Tailed bacteriophages (order Caudovirales) are characterised by an icosahedral capsid, which encloses a double-stranded DNA genome. These phages and herpesviruses share a common assembly pathway for prohead formation and genome packaging. In both viruses, DNA incorporation and ejection is mediated by a machinery built by similar components, including the portal protein and a motor protein complex called terminase, which provides the energy for DNA translocation and has nuclease activity. The portal is a large oligomeric ring-shaped protein located at a unique pentameric vertex of the capsid. It acts as an initiator for capsid assembly and it is also a critical part of the DNA packaging and ejection machinery. In phages, the portal is also involved in tail assembly.

Using X-ray crystallography and high-resolution cryo-electron microscopy, we have solved the structure of a bacteriophage portal, in different conformations, and a tail complex. Our findings point to a molecular mechanism for DNA retention and ejection. A herpesvirus terminase subunit and a portal have also been solved and will be compared with their phage equivalent parts.
Date: 10 July 2019, 16:00 (Wednesday, 11th week, Trinity 2019)
Venue: Wellcome Trust Centre for Human Genetics, Headington OX3 7BN
Venue Details: Meeting rooms A & B
Speaker: Prof Miquel Coll ( IRB Barcelona)
Organising department: Wellcome Trust Centre for Human Genetics
Organiser: Agata Krupa (Wellcome Centre for Human Genetics, University of Oxford)
Organiser contact email address: strubiadmin@strubi.ox.ac.uk
Hosts: Prof Yvonne Jones (University of Oxford), Prof David Stuart (University of Oxford)
Part of: Strubi seminars
Booking required?: Not required
Audience: Members of the University only
Editor: Agata Krupa