Structure and stability of icosahedral particles of a covalent coat protein dimer of bacteriophage MS2

• Particles formed by the bacteriophage MS2 coat protein mutants with insertions in their surface loops induce a strong immune response against the inserted epitopes. The covalent dimers created by fusion of two copies of the coat protein gene are more tolerant to various insertions into the surface loops than the single subunits. We determined a 4.7Å-resolution crystal structure of an icosahedral particle assembled from covalent dimers and compared its stability to wildtype virions. The structure resembled the wildtype virion except for the intersubunit linker regions. The covalent dimer orientation was random with respect to both icosahedral twofold and quasi-twofold symmetry axes. A fraction of the particles was unstable in phosphate buffer because of assembly defects. Our results provide a structural background for design of modified covalent coat-protein dimer subunits for use in immunization.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Keyword

Virus

Structure

Assembly

Stability

Biology

Biologi

Publication and Content Type

ref (subject category)

art (subject category)