Packaging of up to 240 subunits of a 17 kDa nuclease into the interior of recombinant hepatitis B virus capsids

FEBS Lett. 2000 Sep 15;481(2):169-76. doi: 10.1016/s0014-5793(00)01927-x.

Abstract

The icosahedral nucleocapsid of hepatitis B virus (HBV) consists of multiple subunits of a single 183 amino acids (aa) core protein encasing the viral genome. However, recombinant core protein alone also forms capsid-like particles. We have recently shown that a 238 aa protein centrally inserted into the core protein can be displayed on the particle surface. Here we demonstrate that replacement of the C-terminal basic domain by the 17 kDa Staphylococcus aureus nuclease also yields particles but that in these the foreign domains are located in the interior. The packaged nuclease is enzymatically active, and the chimeric protein forms mosaic particles with the wild-type core protein. Hence the HBV capsid is useful as a molecular platform which, dependent on the fusion site, allows foreign protein domains to either be packaged into or be exposed on the exterior of the particle. These results are of relevance for the use of the HBV capsid as a vaccine carrier, and as a target for antiviral therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Calcium / pharmacology
  • Capsid / chemistry
  • Capsid / genetics
  • Capsid / metabolism*
  • Capsid / ultrastructure*
  • Catalysis / drug effects
  • Centrifugation, Density Gradient
  • Hepatitis B virus / genetics
  • Hepatitis B virus / metabolism*
  • Hepatitis B virus / ultrastructure
  • Micrococcal Nuclease / genetics
  • Micrococcal Nuclease / metabolism*
  • Micrococcal Nuclease / ultrastructure
  • Microscopy, Electron
  • Models, Molecular
  • Molecular Sequence Data
  • Mutation
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism
  • Recombinant Fusion Proteins / ultrastructure
  • Staphylococcus aureus / enzymology
  • Vaccines, Synthetic / biosynthesis
  • Vaccines, Synthetic / genetics
  • Vaccines, Synthetic / metabolism
  • Vaccines, Synthetic / ultrastructure
  • Viral Vaccines / biosynthesis*
  • Viral Vaccines / chemistry
  • Viral Vaccines / genetics
  • Viral Vaccines / metabolism
  • Virus Assembly*

Substances

  • Recombinant Fusion Proteins
  • Vaccines, Synthetic
  • Viral Vaccines
  • Micrococcal Nuclease
  • Calcium