Development of an antimicrobial peptide-based biosensor for the monitoring of bacterial contaminations

Nisin is a cationic amphiphilic peptide consisting of 34 amino acids with a cluster of hydrophobic residues at the N-terminus and hydrophilic residues at the C-terminus. The mechanism of its action is based on its ability to attach to the bacteria cell membrane before to then cause cell lysis. This antimicrobial peptide was used as biological molecule for the development of a novel impedimetric label-free biosensor for the monitoring of bacterial contamination. The binding affinities of Nisin immobilized with its N-terminus and C-terminus were compared, highlighting the capability of the last configuration to obtain the best analytical performance of the developed biosensor when non-pathogenic Escherichia Coli O157:H7 and Listeria innocua cells were investigated.