| abstract |
The present invention relates to a safe non-virulent Yersinia enterocolitica mutant strain for delivering heterologous proteins in target cells carrying mutations in at least one of the effector genes yopH, yopO, yopP, yopE, yopM, yopT genes and at least one additional mutation in the invasin genes chosen from yadA and/or inv. The present invention also relates to a safe non-virulent Yersinia enterocolitica mutant strain for delivering heterologous proteins in target cells according to claim 1 carrying mutations in all effector genes yopH, yopO, yopP, yopE, yopM, yopT genes and at least one additional mutation in the invasin genes chosen from yadA and/or inv. The present invention also relates to an expression vector for delivering a heterologous protein into a target cell using a Yersinia enterocolitica mutant strain according to any of the claims 1 to 4, which comprises in the 5' to 3' direction :(a) a promoter of a Yersinia virulon gene, (b) a first DNA sequence encoding a delivery signal from a Yersinia effector protein, operably linked to said promoter; and, (c) a second DNA sequence coding for said heterologous protein, fused in frame to the 3' end of said first DNA sequence. The present invention further relates to methods and compositions comprising (the use of) the afore-mentioned mutant strains and expression vectors. |