Abstract:Listeria monocytogenes (LM) is a human-animal Gram-positive bacterium with a wide range of adaptations to the external environment. In order to understand the regulatory role of sRNA rli82 on the environmental adaptability and biofilm generation of LM. In this study, the rli82 gene deletion mutant strain LM- Δrli82 and the complementation strain LM- Δrli82/rli82 were constructed using homologous recombination technology and the differences in growth and biofilm generation of these strains under different stress environment were determined, respectively. Moreover, bioinformatics was used to predict the potential target genes regulated by rli82, and the transcript levels of genes related to environmental stress and biofilm formation were measured by qPCR. The results showed that rli82 gene owns 70 bp in length, with a secondary structure of 2 neck ring. The potential target gene was opuCC. LM- Δrli82 significantly enhanced environmental adaptation capacity under different osmotic pressure (4% and 8% NaCl) when compared to LM EGD-e and LM- Δrli82/rli82. The environmental adaptation capacity was significantly lower under stress conditions of 3.8% ethanol, pH4, pH9 and 30 ℃ . However, the biofilm formation of the 3 strains was not significantly different. The qPCR showed a significant decrease in the relative expression of genes related to environmental stress but no significant difference in biofilm related genes. The results demonstrate that the sRNA rli82 plays an important role in regulating the adaptive capacity of LM to environmental stress, and set a foundation for studying the molecular mechanism of sRNA rli82 regulating environmental stress in LM.
季春辉, 郭蕴, 王立霞, 宁程程, 李娜, 乔军, 孟庆玲, 才学鹏. sRNA rli82 分子特征及其对单核细胞增生李斯特菌环境应激和生物被膜形成的调控作用[J]. 农业生物技术学报, 2022, 30(5): 990-998.
JI Chun-Hui, GUO Yun, WANG Li-Xia, NING Cheng-Cheng, LI Na, QIAO Jun MENG Qing-Ling, CAI Xue-Peng. Molecular Characterization of sRNA rli82 and Its Regulation Roles in Environmental Stress and Biofilm Formation in Listeria monocytogenes. 农业生物技术学报, 2022, 30(5): 990-998.
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