title: Architecture of a dsDNA viral capsid in complex with its maturation protease.
abstract: Most double-stranded DNA (dsDNA) viruses, including bacteriophages and herpesviruses, rely on a staged assembly process of capsid formation. A viral protease is required for many of them to disconnect scaffolding domains/proteins from the capsid shell, therefore priming the maturation process. We used the bacteriophage HK97 as a model system to decipher the molecular mechanisms underlying the recruitment of the maturation protease by the assembling procapsid and the influence exerted onto the latter. Comparisons of the procapsid with and without protease using single-particle cryoelectron microscopy reconstructions, hydrogen/deuterium exchange coupled to mass spectrometry, and native mass spectrometry demonstrated that the protease interacts with the scaffolding domains within the procapsid interior and stabilizes them as well as the whole particle. The results suggest that the thermodynamic consequences of protease packaging are to shift the equilibrium between isolated coat subunit capsomers and procapsid in favor of the latter by stabilizing the assembled particle before making the process irreversible through proteolysis of the scaffolding domains.
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: David
authors.initials: D
authors.lastname: Veesler
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Khayat
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Srinath
authors.initials: S
authors.lastname: Krishnamurthy
authors.affiliation: Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands; Netherlands Proteomics Centre Padualaan 8, 3584CH, Utrecht, The Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: Snijder
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Rick K
authors.initials: RK
authors.lastname: Huang
authors.affiliation: Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands; Netherlands Proteomics Centre Padualaan 8, 3584CH, Utrecht, The Netherlands.
authors.forename: Albert J R
authors.initials: AJ
authors.lastname: Heck
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Ganesh S
authors.initials: GS
authors.lastname: Anand
authors.affiliation: Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA. Electronic address: jackj@scripps.edu.
authors.forename: John E
authors.initials: JE
authors.lastname: Johnson
mesh_terms: D001435:Bacteriophages / Q000737:chemistry*; D002213:Capsid / Q000737:chemistry*; D017899:Caudovirales / Q000201:enzymology; D020285:Cryoelectron Microscopy; D004247:DNA / Q000737:chemistry*; D013058:Mass Spectrometry; D008958:Models, Molecular; D010447:Peptide Hydrolases / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D017434:Protein Structure, Tertiary; D040901:Proteomics; D013816:Thermodynamics
chemical_list: D010455:Peptides; D004247:DNA; D010447:Peptide Hydrolases