Extremely stable various human virus nucleocapsid proteins for viral diagnostics

Nucleocapsid proteins are the major antigenic determinants of infectious disease causing viruses. A substantial progress has been achieved in production of native recombinant viral nucleoproteins in yeasts. Full-length viral nucleocapsid proteins (NPs) were expressed in yeast Saccharomyces cerevisiae or Pichia pastoris at high level. The proteins are assembled into nucleocapsid-like particles (NLPs) in yeast cells and were purified under native conditions, using ultracentrifugation in CsCl gradients. All our products are constantly checked by various analytical methods including electron microscopy (EM). An example EM picture of one of our nucleoprotein products is given below.


Figure. Electron microscopy image of purified yeast-expressed measles nucleocapsid protein product. Nucleocapsid-like particles exhibit typical “herring-bone” morphology, which are similar to that of native viral nucleocapsids.

BALTYMAS produces a range of human virus nucleocapsid proteins including measles, mumps, respiratory syncytial virus, different types of parainfluenza and influenza virus. Optimized production processes result in extremely stable final protein preparations with excellent reproducibility between different lots. Improved nucleoprotein products are stable both in terms of partial degradation and long term stability during storage. Moreover, most of our yeast-derived nucleoproteins correspond to analogue native viral proteins in regard of their post-translational modifications, such as phosphorylation or N-terminal processing.

Also, products with improved reactivity in immunoassays were developed for all nucleoproteins of several viruses listed above. In some cases it depends on the extent of nucleoprotein modification (phosphorylation, etc), however also different degree of oligomerization is often important for higher reactivity of these recombinant proteins. Therefore, purified recombinant NPs are excellent tools for development of diagnostic assays for viral infections.

For most nucleoproteins different formulations including glycerol stock and lyophilized products are available. This enables flexible use of our products in various possible applications. Our proteins are usually purified to >90% purity, but for influenza nucleoproteins there were also highly pure >95% products developed for special applications. Taken together, we hope anyone can find here nucleoprotein product suitable for intended work.

Check our products for nucleoproteins of different viruses: