Transcriptomic analysis of the antibacterial mechanism of ε-polylysine-functionalized magnetic composites against Alicyclobacillus acidoterrestris and its application in apple juice.

ABSTRACT

BACKGROUND: Alicyclobacillus acidoterrestris is a common microorganism in fruit juice. It can produce off-odor metabolites and has been considered to be an important factor in juice contamination. Thus, the development of new strategy for the control of A. acidoterrestris has important practical significance. The primary objective of this work was to assess the antibacterial performance of ε-polylysine-functionalized magnetic composites (Fe3O4@MoS2@PAA-EPL) in apple juice and its effect on juice quality. Moreover, the molecular mechanism of Fe3O4@MoS2@PAA-EPL against A. acidoterrestris was explored by RNA sequencing (RNA-Seq). RESULTS: Experimental results indicated that the synthesized composites possessed the ability to inhibit the viability of A. acidoterrestris vegetative cells and spores. Besides, investigation on the quality of apple juice incubated with Fe3O4@MoS2@PAA-EPL implied that the fabricated composites displayed negligible adverse effects on juice quality. In addition, the results of RNA-Seq demonstrated that 833 differentially expressed genes (DEGs) were identified in Fe3O4@MoS2@PAA-EPL-treated A. acidoterrestris, which were associated with translation, energy metabolism, amino acid metabolism, membrane transport and cell integrity. CONCLUSION: These results suggested that the treatment of Fe3O4@MoS2@PAA-EPL disrupted energy metabolism, repressed cell wall synthesis and caused membrane transport disorder of bacterial cells. This work provides novel insights into the molecular antibacterial mechanism for ε-polylysine-functionalized magnetic composites against A. acidoterrestris. © 2024 Society of Chemical Industry.