Efficacy of nisin derivatives with improved biochemical characteristics, alone and in combination with endolysin PlyP100 to control Listeria monocytogenes in laboratory-scale Queso Fresco

Nisin is an antimicrobial peptide that commonly used as a food preservative and capable of inhibiting the pathogen Listeria monocytogenes. However, nisin ineffective in controlling L. monocytogenes Queso Fresco (QF). To address challenge, this work, we synthetic biology strategies to create series A derivatives by substituting residues 27, 30, 31 32 with positively charged amino acids (H, K R). Our results showed exhibited reduced antilisterial activity vitro compared A; however, they were all more stable under QF-like experimental conditions (pH 7 + 22% milk fat), notably H27/31K. Compared A, H31K V32K slight improvement QF H27/31K was able reduce initial population up 1.5 Log CFU/g. isolates similar susceptibility or after 14 days exposure QF. Notably, when combined endolysin PlyP100, application resulted non-enumerable levels cold storage. highlight potential bioengineered for stabilized enhanced control