Abstract：
Effectively managing foodborne pathogens is imperative in food processing, where probiotics play a crucial role in pathogen control. This study focuses on the Lactiplantibacillus plantarum AR113 and its gene knockout strains, exploring their antimicrobial properties against Escherichia coli O157:H7 and Staphylococcus aureus. Antimicrobial assays revealed that the inhibitory effect of AR113 increases with its growth and the potential bacteriostatic substance is acidic. AR113Δldh, surpassed AR113Δ0273&2024, exhibited a complete absence of bacteriostatic properties, which indicates that lactic acid is more essential than acetic acid in the bacteriostatic effect of AR113. However, the exogenous acid validation test affirmed the equivalent superior bacteriostatic effect of lactic acid and acetic acid. Notably, AR113 has high lactate production and deletion of the ldh gene not only lacks lactate production but also affects acetic production. This underscores the ldh gene\'s pivotal role in the antimicrobial activity of AR113. In addition, among all the selected knockout strains, AR113ΔtagO and ΔccpA also had lower antimicrobial effects, suggesting the importance of tagO and ccpA genes of AR113 in pathogen control. This study contributes insights into the antimicrobial potential of AR113 and stands as the pioneering effort to use knockout strains for comprehensive bacteriostatic investigations.
摘要：
有效管理食源性致病菌在食品加工中势在必行,益生菌在病原体控制中起着至关重要的作用。本研究主要针对植物乳杆菌AR113及其基因敲除菌株,探索其对大肠杆菌O157：H7和金黄色葡萄球菌的抗菌性能。抗菌实验表明，AR113的抑制作用随其生长而增加，潜在的抑菌物质为酸性。AR113Δldh,超过AR113Δ0273和2024，表现出完全没有抑菌特性，这表明在AR113的抑菌效果中，乳酸比乙酸更重要。然而,外源酸验证试验肯定了乳酸和乙酸的等效优越抑菌后果。值得注意的是,AR113具有高乳酸产量,并且ldh基因的缺失不仅缺乏乳酸产量而且影响乙酸产量。这强调了ldh基因在AR113抗菌活性中的关键作用。此外,在所有选定的敲除菌株中，AR113ΔtagO和ΔccpA也具有较低的抗菌作用，提示AR113的tagO和ccpA基因在病原体控制中的重要性。这项研究有助于深入了解AR113的抗菌潜力，并且是使用敲除菌株进行全面抑菌研究的开创性努力。
