Risøen P A, Håvarstein L S, Diep D B, Nes I F
Department of Biotechnological Sciences, Agricultural University of Norway, As.
Mol Gen Genet. 1998 Aug;259(2):224-32. doi: 10.1007/pl00008627.
In Lactobacillus plantarum C11, bacteriocin production has previously been shown to be an inducible process, in which a secreted peptide, produced by the host itself, is involved. The inducing factor, designated plantaricin A (PlnA), is a bacteriocin-like peptide encoded by a gene (plnA) located on the same operon as the genes for a two-component regulatory system (plnBCD). This system consists of a histidine kinase (PlnB) and two response regulators (PlnC,D), and belongs to a recently defined subfamily of two-component regulatory systems, which are activated by secreted peptide pheromones through a quorum-sensing mechanism. We show here that the two response regulators PlnC and PlnD bind specifically to imperfect direct repeats found within the adjacent promoter of the plnABCD operon, and to similar sequences found within the promoter regions of two nearby operons containing bacteriocin structural genes (plnEFI and plnJKLR). Binding of PlnC and PlnD was increased two to three fold in the presence of acetyl phosphate. The results suggest that bacteriocin synthesis in L. plantarum C11 is regulated by the DNA-binding activity of the two response regulators PlnC and PlnD.
在植物乳杆菌C11中，先前已证明细菌素的产生是一个诱导过程，其中宿主自身产生的一种分泌肽参与其中。诱导因子被命名为植物乳杆菌素A（PlnA），是一种类细菌素肽，由位于与双组分调节系统（plnBCD）基因相同操纵子上的一个基因（plnA）编码。该系统由一个组氨酸激酶（PlnB）和两个反应调节因子（PlnC、D）组成，属于最近定义的双组分调节系统亚家族，该亚家族通过群体感应机制被分泌的肽信息素激活。我们在此表明，两个反应调节因子PlnC和PlnD特异性结合到plnABCD操纵子相邻启动子内发现的不完全直接重复序列，以及在两个附近含有细菌素结构基因的操纵子（plnEFI和plnJKLR）启动子区域内发现的类似序列。在乙酰磷酸存在的情况下，PlnC和PlnD的结合增加了两到三倍。结果表明，植物乳杆菌C11中细菌素的合成受两个反应调节因子PlnC和PlnD的DNA结合活性调控。
