Expression of the gene for vaccinia virus 36K nonstructural protein in Escherichia coli and study of the protective properties of expression products

: The nonstructural 36K protein of vaccinia virus (VV) mapped in HindIII-P and HindIII-J fragments of VV strain L-IVP has been expressed in E. coli as a fusion protein. The products of 36K gene preserved the antigen homology with the native protein 36K and the capacity to bind specific immunoglobulins of rabbit antiVV serum. The protective properties of 36K gene products and their joint effect with the immunodominant protein 35K were investigated. The non-structural 36K gene products showed no protective activity, but increased the production of specific antibodies in mice immunized with a mixture of both protein preparations, this increase being compatible with that observed after immunization with the inactivated virus preparations.