Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China.
State Key Laboratory of Plateau Ecology and Agriculture, Qinghai Academy of Animal and Veterinary Sciences, Qinghai University, Xining, China.
J Food Sci. 2022 Jun;87(6):2718-2731. doi: 10.1111/1750-3841.16148. Epub 2022 Apr 26.
Bacteriocins inhibit various foodborne bacteria in planktonic and biofilm forms. However, bacteriocins with antibacterial and antibiofilm activity against Staphylococcus argenteus, a pathogen that can cause food poisoning, are still poorly known. Here, the novel bacteriocin LSB1 derived from Lactobacillus plantarum CGMCC 1.12934 was purified and characterized extensively. LSB1 had a molecular weight of 1425.78 Da and an amino acid sequence of YIFVTGGVVSSLGK. Moreover, LSB1 exhibited excellent stability under heat and acid-base stress and presented sensitivity to pepsin and proteinase K. LSB1 exhibited an extensive antimicrobial spectrum against both Gram-positive and Gram-negative bacteria. Minimum inhibitory concentration of LSB1 against S. argenteus_70917 was 10.36 µg/ml, which was lower than that of most of the previously found bacteriocins against Staphylococcus strains. Furthermore, LSB1 significantly inhibited S. argenteus_70917 planktonic cells (p < 0.01) and decreased their viability. Scanning electron microscopy analysis revealed that cell membrane permeability of S. argenteus_70917 upon exposure to LSB1 showed leakage of cytoplasmic contents and rupture, leading to cell death. In addition, biofilm formation ability of S. argenteus_70917 was significantly (p < 0.01) impaired by LSB1, with the percent inhibition of 35% at 10 µg/ml and 80% at 20 µg/ml. Overall, this study indicates that LSB1 can be considered a potential antibacterial agent in the control of S. argenteus in both planktonic and biofilm states. PRACTICAL APPLICATION: Foodborne pathogenic bacteria, such as Staphylococcus argenteus, and their biofilms represent potential risks for food safety. In recent years, customers' demand for "natural" products has increased food control. This study describes the novel bacteriocin LSB1 produced by the lactic acid bacterium species Lactobacillus plantarum. LSB1 showed strong antibacterial and antibiofilm activity against S. argenteus as well as thermal and acid-alkaline stability. Furthermore, the mechanisms of action of LSB1 on S. argenteus were preliminarily explored. These results indicate that LSB1 might be potentially used as an effective and natural food preservative.
细菌素可抑制浮游和生物膜形式的各种食源性病原体。然而，针对金黄色葡萄球菌（一种可引起食物中毒的病原体）具有抗菌和抗生物膜活性的细菌素仍然知之甚少。在这里，从植物乳杆菌 CGMCC 1.12934 中分离得到的新型细菌素 LSB1 进行了广泛的纯化和表征。LSB1 的分子量为 1425.78 Da，氨基酸序列为 YIFVTGGVVSSLGK。此外，LSB1 在热酸碱胁迫下表现出极好的稳定性，并对胃蛋白酶和蛋白酶 K 敏感。LSB1 对革兰氏阳性和革兰氏阴性细菌具有广泛的抗菌谱。LSB1 对金黄色葡萄球菌_70917 的最小抑菌浓度为 10.36 µg/ml，低于大多数先前发现的针对金黄色葡萄球菌菌株的细菌素。此外，LSB1 显著抑制金黄色葡萄球菌_70917 浮游细胞（p<0.01）并降低其活力。扫描电子显微镜分析显示，LSB1 暴露后金黄色葡萄球菌_70917 的细胞膜通透性显示细胞质内容物泄漏和破裂，导致细胞死亡。此外，LSB1 显著（p<0.01）抑制金黄色葡萄球菌_70917 的生物膜形成能力，在 10 µg/ml 时抑制率为 35%，在 20 µg/ml 时抑制率为 80%。总体而言，这项研究表明，LSB1 可被视为控制浮游和生物膜状态下金黄色葡萄球菌的潜在抗菌剂。
食源性病原体，如金黄色葡萄球菌及其生物膜，对食品安全构成潜在风险。近年来，客户对“天然”产品的需求增加了食品控制。本研究描述了由植物乳杆菌产生的新型细菌素 LSB1。LSB1 对金黄色葡萄球菌具有较强的抗菌和抗生物膜活性，并且具有热稳定性和酸碱稳定性。此外，还初步探讨了 LSB1 对金黄色葡萄球菌的作用机制。这些结果表明，LSB1 可能被潜在用作有效的天然食品防腐剂。
