Bardischewski T, Vallo S, Nitzsche R, Chanos P, Sieksmeyer T, Stühmeier-Niehe C, Aganovic K, Hertel C
DIL, German Institute of Food Technologies, Prof.-von-Klitzing-Str. 7, Quakenbrück, 49160, Germany.
Elea Technology GmbH, Professor-von Klitzing Str. 9, Quakenbrück, 49610, Germany.
BMC Microbiol. 2025 Jul 14;25(1):435. doi: 10.1186/s12866-025-04161-7.
Intracellular enzymes released during bacterial cell lysis contribute to the development of flavor and texture in fermented foods through the hydrolysis of proteins and fats. In fermented meat products this takes place only late in the fermentation process which limits its effect. Therefore, time-controlled cell lysis constitutes a potentially valuable tool for enhancing sensory characteristics of the final product. This study investigated the prophage-induced, time-delayed bacterial cell lysis in TMW 1.1290 by using different stress conditions, including those generated by food technologies, like pulsed electric fields (PEF) and high hydrostatic pressure (HHP).
UV light induced transient cell lysis, confirmed by a 2102-fold increase of expression of the prophage amidase gene, as determined by Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR). The effect of oxidative stress chemicals like menadione and hydrogen peroxide was far more pronounced, causing evident cell lysis, although probably differing in their modes of action. Although PEF treatment and HHP are known to cause direct or indirect oxidative stress in cells, their applications on cell suspensions at sublethal conditions were not able to cause cell lysis induction under the experimental conditions used.
Prophage-mediated cell lysis in TMW 1.1290 can be induced by UV light and mitomycin C, while H₂O₂ and menadione showed prophage activation potential but significantly inhibited growth. Food technologies like PEF and HHP were ineffective at inducing prophage-mediated cell lysis despite causing sublethal injury, requiring further study of treatment parameters.
细菌细胞裂解过程中释放的胞内酶通过蛋白质和脂肪的水解作用，有助于发酵食品风味和质地的形成。在发酵肉制品中，这种情况仅在发酵后期发生，这限制了其效果。因此，时间控制的细胞裂解是增强最终产品感官特性的潜在有价值工具。本研究通过使用不同的应激条件，包括食品技术产生的应激条件，如脉冲电场（PEF）和高静水压（HHP），研究了TMW 1.1290中前噬菌体诱导的、时间延迟的细菌细胞裂解。
紫外线诱导了短暂的细胞裂解，通过逆转录定量聚合酶链反应（RT-qPCR）测定，前噬菌体酰胺酶基因的表达增加了2102倍，证实了这一点。甲萘醌和过氧化氢等氧化应激化学物质的作用更为显著，导致明显的细胞裂解，尽管它们的作用方式可能不同。虽然已知PEF处理和HHP会在细胞中引起直接或间接的氧化应激，但在实验条件下，它们在亚致死条件下对细胞悬液的应用未能诱导细胞裂解。
紫外线和丝裂霉素C可诱导TMW 1.1290中前噬菌体介导的细胞裂解，而H₂O₂和甲萘醌显示出前噬菌体激活潜力，但显著抑制生长。尽管PEF和HHP等食品技术会造成亚致死损伤，但在诱导前噬菌体介导的细胞裂解方面无效，需要进一步研究处理参数。
