Identification of inducible promoters

Many LAB are generally regarded as save and thus they are member of the group of GRAS microorganisms. This means that they are not harmful to human in contrast to the widely used bacterium Escherichia coli. The GRAS-status makes LAB perfectly suitable for medical applications such as the production of antigens, growth factors or antibodies. The aim of this project is the identification of regulatory DNA-elements in Lactic acid bacteria in order to use these microorganisms for biotechnological approaches. For the identification of inducible promoters, a DNA-library should be constructed in E. coli. Genomic DNA fragments of L. buchneri are therefore cloned in front of a reportergene. In the case of promoter activity, the reportergene is expressed and cells can be easily screened for promoter containing fragments. By altering environmental conditions (heat shock, cold shock) promoter fragments are then tested for inducibility.