College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China.
College of Food Science and Engineering, Shandong Agricultural University, Tai'an Shandong, 271018, China; National R&D Center for Beef Processing Technology, Tai'an, Shandong, 271018, China; International Joint Research Lab (China and Greece) of Digital Transformation as an Enabler for Food Safety and Sustainability, Tai'an, Shandong, 271018, China.
Food Microbiol. 2024 Jun;120:104494. doi: 10.1016/j.fm.2024.104494. Epub 2024 Feb 15.
Bacterial volatile compounds (BVCs) facilitate interspecies communication in socio-microbiology across physical barriers, thereby influencing interactions between diverse species. The impact of BVCs emitted from Pseudomonas on the biofilm formation characteristics of Listeria monocytogenes within the same ecological niche has been scarcely investigated under practical conditions of food processing. The objective of this study was to explore the motility and biofilm formation characteristics of L. monocytogenes under the impact of Pseudomonas BVCs. It was revealed that BVCs of P. fluorescens, P. lundensis, and P. fragi significantly promoted swimming motility of L. monocytogenes (P < 0.05). As evidenced by crystal violet staining, the L. monocytogenes biofilms reached a maximum OD value of approximately 3.78 at 4 d, which was 0.65 units markedly higher than that of the control group (P < 0.05). Despite a decrease in adherent cells of L. monocytogenes biofilms among the BVCs groups, there was a remarkable increase in the abundance of extracellular polysaccharides and proteins with 3.58 and 4.90 μg/cm, respectively (P < 0.05), contributing to more compact matrix architectures, which suggested that the BVCs of P. fluorescens enhanced L. monocytogenes biofilm formation through promoting the secretion of extracellular polymers. Moreover, the prominent up-regulated expression of virulence genes further revealed the positive regulation of L. monocytogenes under the influence of BVCs. Additionally, the presence of BVCs significantly elevated the pH and TVB-N levels in both the swimming medium and biofilm broth, thereby exhibiting a strong positive correlation with increased motility and biofilm formation of L. monocytogenes. It highlighted the crucial signaling regulatory role of BVCs in bacterial interactions, while also emphasizing the potential food safety risk associated with the hitchhiking behavior of L. monocytogenes, thereby shedding light on advancements in control strategies for food processing.
细菌挥发性化合物 (BVCs) 促进了社会微生物学中跨越物理障碍的种间通讯，从而影响了不同物种之间的相互作用。在食品加工的实际条件下，很少研究假单胞菌产生的 BVC 对同一生态位内单核细胞增生李斯特菌生物膜形成特性的影响。本研究旨在探讨 BVCs 对单核细胞增生李斯特菌运动和生物膜形成特性的影响。结果表明，荧光假单胞菌、伦德斯氏假单胞菌和脆弱拟杆菌的 BVCs 显著促进了单核细胞增生李斯特菌的泳动性（P<0.05）。结晶紫染色结果表明，单核细胞增生李斯特菌生物膜在第 4 天达到约 3.78 的最大 OD 值，比对照组高 0.65 个单位（P<0.05）。尽管 BVCs 组单核细胞增生李斯特菌生物膜的附着细胞减少，但细胞外多糖和蛋白质的丰度分别显著增加了 3.58 和 4.90μg/cm（P<0.05），这有助于形成更紧凑的基质结构，表明荧光假单胞菌的 BVCs 通过促进细胞外聚合物的分泌来增强单核细胞增生李斯特菌生物膜的形成。此外，毒力基因的显著上调表达进一步揭示了 BVCs 影响下单核细胞增生李斯特菌的正调控作用。此外，BVCs 的存在显著提高了泳动培养基和生物膜培养基中的 pH 和 TVB-N 水平，从而与单核细胞增生李斯特菌的运动性和生物膜形成呈强正相关。这突出了 BVCs 在细菌相互作用中的关键信号调节作用，同时也强调了单核细胞增生李斯特菌搭乘行为所带来的潜在食品安全风险，为食品加工中控制策略的发展提供了启示。
