Team:UI-Indonesia/Project/Killing

From 2014.igem.org

Peptide 1018

Peptide 1018 is a potent broad spectrum antibiofilm substance previously identified as innate defense regulator. Peptide 1018 act by blocking stress responses that lead to biofilm formation mediated by guanosine 5’diphosphate 3’-diphosphate(ppGpp) and guanosine 5’-triphosphate 3’-diphosphate (pppGpp), collectively denoted (p)ppGpp. These act as second messenger response that is triggered by miscellaneous stress condition is highly preserved in both Gram-positive and Gram-negative bacteria. Former studies shows that (p)ppGpp is an important role in biofilm formation, mutants are influencing (p)ppGpp production are biofilm deficient but not fully defective, occasionally forming monolayer biofilm matrix[11].
The peptide 1018 is small peptide consist of 12 amino acid (VRLIVAVRIWRR-NH2). Peptide 1018 is amphipathic cationic peptides have characteristic called cell penetrating peptides that are able to freely move across membrane. So we do not add HlyA secretion tag in the down stream region of circuit.




Peptide 1018 also as safety module

Killing module is also functioned as safety module . The purpose of safety module is to avoid our mutant E.coli still alive when the absence of Vibrio cholerae. The killing module is under T5 constitutive promoter so the enzyme will be produced continuously even there is no quorum sensing signal until the concentration of enzyme reach the toxic concentration of the E.coli cells cause cells death.