Viral polyhedra complexes and methods of use
US8554493B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 28, 2008 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Nov 10, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC12N2720/12022
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Cypoviruses and baculoviruses are notoriously difficult to eradicate because the virus particles are embedded in micron-sized protein crystals called polyhedra. The remarkable stability of polyhedra means that like bacterial spores these insect viruses remain infectious for years in soil. Although these unique in vivo protein crystals have been extensively characterized since the early 1900s, their atomic organization remains elusive. Here we describe the 2 crystal structure of both recombinant and infectious silkworm cypovirus polyhedra determined using 5-12 micron crystals purified from insect cells. These are the smallest crystals yet used for de novo X-ray protein structure determination. It was found that polyhedra are made of trimers of the viral polyhedrin protein and contain nucleotides. Although the shape of these building blocks is reminiscent of some capsid trimers, polyhedrin has a new fold and has evolved to assemble in vivo into 3-D cubic crystals rather than icosahedral shells. The polyhedrin trimers are extensively cross-linked in polyhedra by non-covalent interactions and pack with an exquisite molecular complementarity similar to that of antigen-antibody complexes…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.