An IP-free strain for recombinant proteins production 

Thanks to its proprietary technology COLIBELT®, BGene has constructed a strain equivalent to the widely used BL21(DE3) strain, including for the production of recombinant proteins.

The BL21(DE3) strain contains the DE3 prophage allowing the expression of genes expressed under the control of the T7 promoter.

Several reports mention that this construction could be unstable through spontaneous lysogenic induction.

In order to improve the stability during fermentation, BGene has developed the BELT21 strain. Based on the free-to-operate BL21 strain, the BELT21 strain was constructed integrating into the chromosome the whole system needed for the expression of recombinant proteins (LacI-placUV5-T7RNApol) without the other genes of the DE3 prophage.

Tests realized on the BELT21 by fluorescent assays showed equivalent to increased expression levels compared to those obtained with BL21(DE3).

This strain is currently tested in fermenters to compare its performance to BL21(DE3)

This strain is available from today



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 Belt 21 Documentation