AUTHOR=Jiang Yu-Hang , Xin Wei-Gang , Zhang Qi-Lin , Lin Lian-Bing , Deng Xian-Yu 

TITLE=A Novel Bacteriocin Against Shigella flexneri From Lactiplantibacillus plantarum Isolated From Tilapia Intestine: Purification, Antibacterial Properties and Antibiofilm Activity

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.779315

DOI=10.3389/fmicb.2021.779315

ISSN=1664-302X

ABSTRACT=<p>Few bacteriocins with antibacterial activity against <italic>Shigella flexneri</italic> have been reported. Here, a novel bacteriocin (<italic>LFX01</italic>) produced by <italic>Lactiplantibacillus plantarum</italic> strain LF-8 from the intestine of tilapia was purified and extensively characterized. <italic>LFX01</italic> possesses a molecular weight of 1049.56 Da and an amino acid sequence of I-T-G-G-P-A-V-V-H-Q-A. <italic>LFX01</italic> significantly inhibited <italic>S. flexneri</italic> strain 14 (<italic>S. flexneri</italic>_14) growth. Moreover, it exhibited excellent stability under heat and acid-base stress, and presented sensitivity to a variety of proteases, such as proteinase K, pepsin, and trypsin. The minimum inhibitory concentration (MIC) of <italic>LFX01</italic> against <italic>S. flexneri</italic>_14 was 12.65 μg/mL, which was smaller than that of most of the previously found bacteriocins. Furthermore, <italic>LFX01</italic> significantly inhibited (<italic>p</italic> &lt; 0.05) <italic>S. flexneri</italic>_14 cells and decreased their cell viability. In addition, <italic>LFX01</italic> could significantly (<italic>p</italic> &lt; 0.05) inhibit biofilm formation of <italic>S. flexneri</italic>_14. Scanning electron microscopy analysis presented that the cell membrane permeability of <italic>S. flexneri</italic>_14 was demolished by <italic>LFX01</italic>, leading to cytoplasmic contents leakage and cell rupture death. In summary, a novel bacteriocin of lactic acid bacteria (LAB) was found, which could effectively control <italic>S. flexneri</italic> in both planktonic and biofilm states.</p>