FlexiBac 

The unit has developed an original and patented technology, called FlexiBac, to generate 100% multi-recombinant baculoviruses in a single step.

This technology relies on the use of viral DNA made non-infectious (by deletion of essential genes) and replicated in E. coli cells (by introducing a bacterial origin of replication, mini-F, into the viral genome). This non-infectious viral DNA is called BacMids.

A set of BacMids was constructed by deleting essential genes from the viral DNA. Specific transfer vectors (pVT) are generated, containing (i) a promoter, (ii) an expression cassette to produce the protein of interest, and (iii) a functional copy of the essential gene deleted in the BacMid.

During the transfection of Sf9 cells with a BacMid and pVT vectors, homologous recombination occurs between the BacMid DNA and the pVT vectors, leading to the repair of essential genes and the generation of infectious mono- or multi-recombinant baculoviruses. This system enables the one-step generation of 100% recombinant baculoviruses co-expressing 1 to 6 genes of interest.

Principle of our patented FlexiBac technology

The modulation of recombinant protein expression can be achieved by using different promoters with specific expression patterns, such as cellular promoters, early or late viral promoters, and promoters with low or high transcriptional activity.