Wu Jiangchao, Yu Yigang, Liu Fengsong, Cao Yifang, Ren Jiahao, Fan Yiting, Xiao Xinglong
The College of Life and Geographic Sciences, Kashi University, Kashi 844000, China.
School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Foods. 2025 Jan 8;14(2):171. doi: 10.3390/foods14020171.
is a foodborne pathogen characterized by its robust stress tolerance and ability to form biofilms, which facilitates its survival in powdered infant formula (PIF) processing environments for prolonged periods. Gamma-aminobutyric acid (GABA) is a kind of non-protein amino acid that acts as an osmoprotectant. This study aimed to elucidate the effects of the gene on the survival of , GABA accumulation, and biofilm formation under desiccation, osmotic stress, and acid exposure. A knockout strain of was developed using gene recombination techniques. The GABA content and survival rates of both the wild-type and knockout strains were compared under various stress conditions. Scanning electron microscopy (SEM) was used to observe cellular damage and biofilm formation. Statistical analysis was performed using a one-way analysis of variance (ANOVA). The deletion of resulted in enhanced GABA accumulation under different stress conditions, improving the bacterium's tolerance to desiccation, osmotic pressure, and acid treatment. SEM images revealed that under identical stress conditions, the knockout strain exhibited less cellular damage compared to the wild-type strain. Both strains were capable of biofilm formation under low osmotic pressure stress, but the knockout strain showed higher GABA content, denser biofilm formation, and increased biofilm quantity. Similar trends were observed under acid stress conditions. The gene plays a key role in modulating GABA accumulation, which enhances the stress tolerance and biofilm formation of . These findings provide new insights into the role of GABA in bacterial survival mechanisms and highlight the potential for targeting GABA pathways to control in food processing environments.
是一种食源性病原体，其特点是具有强大的应激耐受性和形成生物膜的能力，这有助于其在婴儿配方奶粉（PIF）加工环境中长期存活。γ-氨基丁酸（GABA）是一种作为渗透保护剂的非蛋白质氨基酸。本研究旨在阐明该基因对在干燥、渗透胁迫和酸暴露条件下的存活、GABA积累以及生物膜形成的影响。利用基因重组技术构建了的基因敲除菌株。比较了野生型和敲除菌株在各种应激条件下的GABA含量和存活率。使用扫描电子显微镜（SEM）观察细胞损伤和生物膜形成。采用单因素方差分析（ANOVA）进行统计分析。基因的缺失导致在不同应激条件下GABA积累增加，提高了细菌对干燥、渗透压和酸处理的耐受性。SEM图像显示，在相同应激条件下，与野生型菌株相比，基因敲除菌株的细胞损伤较小。在低渗透压胁迫下，两种菌株都能够形成生物膜，但基因敲除菌株表现出更高的GABA含量、更密集的生物膜形成和增加的生物膜量。在酸胁迫条件下也观察到类似趋势。该基因在调节GABA积累中起关键作用，从而增强了的应激耐受性和生物膜形成。这些发现为GABA在细菌存活机制中的作用提供了新的见解，并突出了靶向GABA途径以控制食品加工环境中的潜力。
