Overview of Experiments
1. Production Strains
In order to ensure that the bacteria we are working with are really the ones we want to work with, a 16S rDNA PCR was performed.
As an antibiotic resistance will be used in our later experiments to select transformants, we checked for any native antibiotic resistance against ampicillin, kanamycin, tetracyclin and chloramphenicol in an LB agar plate growth test. It turned out that kanamycin was the only antibiotic, against which none of our strains showed any resistance. For this reason, we decided to use only vectors with kanamycin resistance for our later projects.
After this, we prepared electro competent cells from our strains. All of our strains were grown on LB medium.
2. BioBricks
Our BioBricks were designed using the software SnapGene. The original Genes for our B12 binding proteins, and the torA signal sequence were codon optimized for E. coli.
The DNA containing the Genes were synthesized and friendly provided by IDT Integrated DNA Technologies.
In case of MutB, the length of the gene exceeded the maximum length of 2000 bp from IDT. For this reason, we designed two DNA parts, with a natural occurring HindIII restriction site at both ends. We intended to fuse these both genes by ligation. However, after having diffuculties to fuse the genes by ligation, we decided to fuse them by fusion PCR.