Real-Time Assembly of Viruslike Nucleocapsids Elucidated at the Single-Particle Level

Margherita Marchetti, Douwe Kamsma, Ernesto Cazares Vargas, Armando Hernandez García, Paul Van Der Schoot, Renko De Vries, Gijs J.L. Wuite*, Wouter H. Roos

*Corresponding author for this work

Research output: Contribution to JournalArticleAcademicpeer-review


While the structure of a multitude of viral particles has been resolved to atomistic detail, their assembly pathways remain largely elusive. Key unresolved issues are particle nucleation, particle growth, and the mode of genome compaction. These issues are difficult to address in bulk approaches and are effectively only accessible by the real-time tracking of assembly dynamics of individual particles. This we do here by studying the assembly into rod-shaped viruslike particles (VLPs) of artificial capsid polypeptides. Using fluorescence optical tweezers, we establish that small oligomers perform one-dimensional diffusion along the DNA. Larger oligomers are immobile and nucleate VLP growth. A multiplexed acoustic force spectroscopy approach reveals that DNA is compacted in regular steps, suggesting packaging via helical wrapping into a nucleocapsid. By reporting how real-time assembly tracking elucidates viral nucleation and growth principles, our work opens the door to a fundamental understanding of the complex assembly pathways of both VLPs and naturally evolved viruses.

Original languageEnglish
Pages (from-to)5746-5753
Number of pages8
JournalNano Letters
Issue number8
Early online date1 Aug 2019
Publication statusPublished - 14 Aug 2019


  • acoustic force spectroscopy
  • artificial virus
  • biophysics
  • optical tweezers
  • physical virology
  • Self-assembly


Dive into the research topics of 'Real-Time Assembly of Viruslike Nucleocapsids Elucidated at the Single-Particle Level'. Together they form a unique fingerprint.

Cite this