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Cronobacter sakazakii (Cs) is a typical foodborne bacterium that infect powdered infant formula (PIF) worldwide. In this study, a recombinant antimicrobial peptide, branded as Funme peptide (FP)was applied to protect PIF from Cs contamination. The result from the antimicrobial activity assay showed that the minimum inhibitory concentration (MIC) of BMAP-27 peptide, FP and Ampicillin against Cs were 250.0, 125.0 and 15.6 μg/mL, respectively, indicating FP possessed higher MIC than that of Ampicillin, and lower MIC than that of BMAP-27. The minimum biofilm eradication concentration (MBEC) assay showed that FP at 2 × MIC (250.0 μg/mL) could completely eradicated Cs biofilms. The antibacterial activity of FP might be due to the increasing permeability and the release of cytoplasmic β-galactosidase of Cs. The results acquired from transmission electron microscopy and scanning electron microscopy indicated that FP induced the disruption and dysfunction of cell walls and membranes. Moreover, safety assay showed that FP had low cytotoxicity to human erythrocytes. The present study investigated the antibacterial effects and mechanisms of FP against Cs, providing promising evidence to apply this novel antimicrobial agent against Cs contamination in foods and food processing facilities.

We used suppression subtractive hybridization (SSH) to identify submergence-induced genes from the submergence-tolerant rice cultivar, FR13A. These genes putatively encode four proteins including a cation transport protein ( OsCTP ), monogalactosyl–diacylglycerol synthase, a cold-induced protein and glutathione synthetase. The full-length gene of one upregulated clone, OsCTP was generated by rapid amplification of cDNA ends. The gene comprises 741 bp with an open reading frame of 414 bp (nt 51–464) that encodes a putative protein of 137 amino acids. The theoretical isoelectric point of the putative protein is 5.35 and the molecular weight is 15.2 kDa. Six exons and five introns of the OsCTP gene correspond to 3582–2296 bp of accession number AAAA01013244 from the rice genome. OsCTP expression is enhanced by submergence as well as stress induced by abscisic acid, salt or drought. OsCTP might encode a novel cation transport protein similar to Escherichia coli ChaC and may be associated with a general defensive response to various environmental stresses.