Department of Food Science and Technology, The Ohio State University, Columbus, Ohio, USA.
PLoS One. 2013 Jul 23;8(7):e70448. doi: 10.1371/journal.pone.0070448. Print 2013.
The formation of Listeria monocytogenes biofilms contributes to persistent contamination in food processing facilities. A microarray comparison of L. monocytogenes between the transcriptome of the strong biofilm forming strain (Bfm(s)) Scott A and the weak biofilm forming (Bfm(w)) strain F2365 was conducted to identify genes potentially involved in biofilm formation. Among 951 genes with significant difference in expression between the two strains, a GntR-family response regulator encoding gene (LMOf2365_0414), designated lbrA, was found to be highly expressed in Scott A relative to F2365. A Scott A lbrA-deletion mutant, designated AW3, formed biofilm to a much lesser extent as compared to the parent strain by a rapid attachment assay and scanning electron microscopy. Complementation with lbrA from Scott A restored the Bfm(s) phenotype in the AW3 derivative. A second microarray assessment using the lbrA deletion mutant AW3 and the wild type Scott A revealed a total of 304 genes with expression significantly different between the two strains, indicating the potential regulatory role of LbrA in L. monocytogenes. A cloned copy of Scott A lbrA was unable to confer enhanced biofilm forming potential in F2365, suggesting that additional factors contributed to weak biofilm formation by F2365.
李斯特菌生物膜的形成导致了食品加工设施中持续的污染。对强生物膜形成菌株（Bfm(s)）Scott A 和弱生物膜形成菌株（Bfm(w)）F2365 的转录组进行了李斯特菌微阵列比较，以鉴定可能参与生物膜形成的基因。在两株菌之间表达差异显著的 951 个基因中，发现了一个 GntR 家族响应调节基因（LMOf2365_0414），命名为 lbrA，在 Scott A 中的表达水平相对 F2365 显著升高。与亲本菌株相比，Scott A 的 lbrA 缺失突变株 AW3 通过快速附着测定和扫描电子显微镜观察到生物膜形成程度大大降低。用来自 Scott A 的 lbrA 进行互补恢复了 AW3 衍生物的 Bfm(s)表型。使用 lbrA 缺失突变株 AW3 和野生型 Scott A 的第二次微阵列评估共发现了两株菌之间表达显著不同的 304 个基因，表明 LbrA 在李斯特菌中具有潜在的调节作用。Scott A lbrA 的克隆拷贝无法在 F2365 中赋予增强的生物膜形成潜力，这表明 F2365 的弱生物膜形成还涉及其他因素。
