The vector pTTB1 is a low copy food grade expression vector for constitutive expression. Selection in B. subtilis is based on the interplay of the endogenous Bacillus toxin EndoA (encoded within the genome of host strains B. subtilis TEA or B. subtilis WEA) and its antitoxin EndoB (vector encoded). For easier handling pTTB1 is designed as B. subtilis / E. coli shuttle vector. The parts of the vector used for cloning with E. coli (E. coli origin and ampicillin resistance cassette) can be eliminated afterwards by restriction enzyme cleavage and religation of the vector. This technique connects the advantage of easy cloning with E. coli with the food grade property of B. subtilis.
- Food grade protein production
- Stable low level expression without addition of any antibiotics
- All DNA contained in the final expression system is derived from B. subtilis
- No endotoxins are produced
- Corresponding protease-deficient strain for secretory protein production is available
The pTTB1 vector and corresponding strains B. subtilis TEA and B. subtilis WEA are available from MoBiTec GmbH (Göttingen)