Antimicrobial peptides have the ability to function as bio-recognition elements in the detection of bacteria. For instance, we showed that Leucocin A, an antimicrobial peptide from class IIa bacteriocins, binds gram-positive Listeria monocytogenes with higher affinity than other gram-positive bacteria like S. aureus, L. innocua, and E. faecalis. The binding was detected using impedance spectroscopy when Leucocin A immobilized on impedance electrodes binds bacteria from a sample. Here we highlight the strength of utilizing Leucocin A as a bio-recognition probe in biosensor platforms and provide details on its application in real-time bacterial detection using electrochemical impedance spectroscopy. A simple new generation impedance array analyzer is utilized that works at very low frequencies to identify interactions between peptide and the target bacteria.
Keywords: Antimicrobial peptide; Bacterial detection; Impedance spectroscopy; Leucocin A; Listeria monocytogenes; Peptide-based biosensors.