Difference between revisions of "Part:BBa K1597000"

Latest revision as of 15:52, 18 September 2015

Salt inducible promoter for B. subtilis

Bacillus subtilis is capable of coping with fluctuating salt concentrations. One of the genes involved is proH, this is an 1-pyrroline-5-caboxylate reductase. A study has shown that this gene is under control of the salt inducible proH promoter (Brill,J et al) (. The salt inducible promoter can be activated by a range of salt concentrations, respectively ranging from 0,1M NaCl up to 1 M. We have cloned this promoter out of the genome of Bacillus subtilis and combined it with tasA (BBa_K1597002) (amyloid-like fibers in the biofilm matrix). To confirm that the salt inducible promoter functions, our construct was placed in B. subtilis NCIB 3610 comI (ΔcomI) with the use of BBa_K823023 . B. subtilis ComI strain with salt inducible PproH promoter and tasA construct (tasA) and B. subtilis ComI (comI) were grown on Msgg media with and without 0,5 M NaCl. After 24 hours thioflavin S (which is an amyloid fiber staining) was added to the biofilms. The biofilms were photographed with white light and fluorescence after 15 min incubation.

With the induction of NaCl, more amyloid fibers are present after 24 hours. This is not the case for the wiltype strain. This indicates that the salt promoter is indeed activated with NaCl, causing an overexpression of tasA.

Another validation was performed with the strain containing the tasA overexpression casette, please look at the page tasA (BBa_K1597002) .

Sequence and Features