Ao Xiaolin, Zhao Jiawei, Yan Junling, Liu Shuliang, Zhao Ke
College of Food Science, Sichuan Agricultural University, Ya'an, Sichuan, China.
Colloge of Resources, Sichuan Agricultural University, Cheng'du', China.
PeerJ. 2020 Aug 3;8:e9639. doi: 10.7717/peerj.9639. eCollection 2020.
(), a dominant strain in traditional fermented foods, is widely used in fermentation industry because of its fast acid production. However, is easily inactivated due to acidity, high temperature and other factors. The formation of biofilm by bacteria can effectively increase environmental tolerance. Therefore, it is important to improve the environmental tolerance of by studying its biofilm formation conditions and regulatory mechanisms.
After determining a suitable NaCl concentration for promoting biofilm formation, was grown with 48 g L NaCl. Differential gene expressions in biofilm vs. planktonic cells were analyzed using RNA sequencing and validated using qPCR.
RS66CD biofilm formation formed highest amount of when grown at 48 g L NaCl. Altogether 447 genes were up-regulated and 426 genes were down-regulated in the biofilm. KEGG pathway analysis showed that genes coding for D-Alanine metabolism, peptidoglycan biosynthesis, two-component system, carbon metabolism, bacterial secretion system, lysine biosynthesis and fatty acid metabolism were crucial for biofilm formation. In addition, eight other genes related to biofilm formation were differentially expressed. Our results provide insights into the differential gene expression involved in biofilm formation, which can help to reveal gene regulation during biofilm formation.
（）是传统发酵食品中的优势菌株，因其产酸速度快而在发酵工业中广泛应用。然而，由于酸度、高温等因素，（）很容易失活。细菌形成生物膜可以有效提高环境耐受性。因此，通过研究其生物膜形成条件和调控机制来提高（）的环境耐受性具有重要意义。
在确定促进生物膜形成的合适NaCl浓度后，将（）在48 g/L NaCl条件下培养。使用RNA测序分析（）生物膜与浮游细胞中的差异基因表达，并通过qPCR进行验证。
RS66CD在48 g/L NaCl条件下生长时形成的生物膜量最高。生物膜中共有447个基因上调，426个基因下调。KEGG通路分析表明，编码D-丙氨酸代谢、肽聚糖生物合成、双组分系统、碳代谢、细菌分泌系统、赖氨酸生物合成和脂肪酸代谢的基因对生物膜形成至关重要。此外，另外8个与生物膜形成相关的基因差异表达。我们的结果为生物膜形成过程中涉及的差异基因表达提供了见解，这有助于揭示（）生物膜形成过程中的基因调控。
