Abstract
BackgroundFoodborne pathogens and their biofilms are considered as one of the most serious problems in human health and food industry. Moreover, safety of foods is a main global concern because of the increasing use of chemical food additives. Ensuring food safety enhances interest in discovery of new alternative compounds such as antimicrobial peptides (AMPs), which can be used as bio-preservatives in the food industry. In this study, the most important antimicrobial peptides of camel milk lactoferrin (lactoferrampin and lactoferricin) were recombinantly expressed in the form of chimeric peptide (cLFchimera) in a food-grade L. lactis strain. P170 expression system was used to express secreted cLFchimera using pAMJ1653 expression vector which harbors a safe (non-antibiotic) selectable marker.ResultsPeptide purification was carried out using Ni-NTA agarose column from culture medium with concentration of 0.13 mg/mL. The results of disk diffusion test revealed that cLFchimera had considerable antimicrobial activity against a number of major foodborne bacteria. Furthermore, this chimeric peptide showed strong and weak inhibitory effect on biofilm formation against P. aeruginosa, S. aureus E. faecalis, and E. coli, respectively. Antioxidant activity and thermal stability of the chimeric peptide was determined. The results showed that cLFchimera had antioxidant activity (IC50: 310 μ/mL) and its activity was not affected after 40 min of boiling. Finally, we evaluated the interaction of the peptide with LPS and DNA in bacteria using molecular dynamic simulation as two main intra and extra cellular targets for AMPs, respectively. Our in silico analysis showed that cLFchimera had strong affinity to both of these targets by positive charged residues after 50 ns molecular dynamic simulation.ConclusionsOverall, the engineered food-grade L. lactis generated in the present study successfully expressed a secreted chimeric peptide with antimicrobial properties and could be considered as a promising bio-preservative in the food industry.
Highlights
Foodborne pathogens and their biofilms are considered as one of the most serious problems in human health and food industry
Transformation of L. lactis and peptide expression L. lactis harboring recombinant pAMJ1653 vector was selected through colony polymerase chain reaction (PCR) by specific primers on a single colony
The results indicated that the medium containing the chimeric peptide had antibacterial effect against E. coli (ATCC 25404), S. aureus (ATCC 15981), S. typhimurium (ATCC 14028), E. faecalis (ATCC 47077), L. monocytogenes (ATCC 19111) and P. aeroginosa PAO1 (Fig. 2)
Summary
Foodborne pathogens and their biofilms are considered as one of the most serious problems in human health and food industry. Ensuring food safety enhances interest in discovery of new alternative compounds such as antimicrobial peptides (AMPs), which can be used as bio-preservatives in the food industry. P170 expression system was used to express secreted cLFchimera using pAMJ1653 expression vector which harbors a safe (non-antibiotic) selectable marker. Foodborne pathogens and their biofilms are one of the serious problems of human health. Shelf life and the safety of food products were enhanced by using natural or controlled microflora, mostly lactic acid bacteria [47] and natural components such as antimicrobial peptides (AMPs) [16]. AMPs have been considered as a new generation of biologically active regulators that can prevent oxidation and microbial degradation in foods [35, 49]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
