摘要:
New promoters are described to drive transcription in meningococcus e.g. for over-expression of protein antigens for retention in membrane vesicles. Modified porA promoters lack the wild-type poly-G sequence which can cause phase variation. Meningococcal rRNA-coding genes (e.g. for 16S rRNA) can be used to drive transcription of a protein-coding gene. These approaches can be used in combination.
摘要:
A first aspect of the invention provides meningococcal outer membrane vesicles in which NHBA is over-expressed. A second aspect of the invention provides meningococcal outer membrane vesicles in which NadA is over-expressed. A third aspect of the invention provides a panel of bacterial strains, each member of which is isogenic except for a single gene which in each strain encodes a different variant of an antigen of interest.
摘要:
The meningococcal fhbp gene (encoding factor H binding protein) is naturally expressed from two independent transcripts by two differentially regulated promoters. In one transcript it is co-expressed with the neighbouring upstream gene from the P nmb1869 promoter. The other transcript is monocistronic and is expressed from its own dedicated promoter, P fhbp , which is activated by the global regulatory protein FNR in response to oxygen-limiting conditions. To increase expression of the monocistronic transcript a constitutively-active FNR mutant is used. The P fhbp promoter can thus be activated, leading to over-expression of FNR-activated genes, such as fhbp.