Diep D B, Håvarstein L S, Nes I F
Laboratory of Microbial Gene Technology, Department of Biotechnological Sciences, Agricultural University of Norway.
J Bacteriol. 1996 Aug;178(15):4472-83. doi: 10.1128/jb.178.15.4472-4483.1996.
Lactobacillus plantarum C11 secretes a small cationic peptide, plantaricin A, that serves as induction signal for bacteriocin production as well as transcription of plnABCD. The plnABCD operon encodes the plantaricin A precursor (PlnA) itself and determinants (PlnBCD) for a signal transducing pathway. By Northern (RNA) and sequencing analyses, four new plantaricin A-induced operons were identified. All were highly activated in concert with plnABCD upon bacteriocin induction. Two of these operons (termed plnEFI and plnJKLR) each encompass a gene pair (plnEF and plnJK, respectively) encoding two small cationic bacteriocin-like peptides with double-glycine-type leaders. The open reading frames (ORFs) encoding the bacteriocin-like peptides are followed by ORFs (plnI and -L, respectively) encoding cationic hydrophobic proteins resembling bacteriocin immunity proteins. On the third operon (termed plnMNOP), a similar bacteriocin-like ORF (plnN) and a putative immunity ORF (either plnM or -P) were identified as well. These findings suggest that two bacteriocins of two-peptide type (mature PlnEF and PlnJK) and a bacteriocin of one-peptide type (mature PlnN) could be responsible for the observed bacteriocin activity. The last operon (termed plnGHSTUV) contains two ORFs (plnGH) apparently encoding an ABC transporter and its accessory protein, respectively, known to be involved in processing and export of peptides with precursor double-glycine-type leaders. Promoter structure was established. A conserved regulatory-like box encompassing two direct repeats was identified in the promoter regions of all five plantaricin A-induced operons. These repeats may serve as regulatory elements for gene expression.
植物乳杆菌C11分泌一种小阳离子肽——植物乳杆菌素A，它作为细菌素产生以及plnABCD转录的诱导信号。plnABCD操纵子编码植物乳杆菌素A前体（PlnA）本身以及信号转导途径的决定因素（PlnBCD）。通过Northern（RNA）和测序分析，鉴定出四个新的植物乳杆菌素A诱导操纵子。在细菌素诱导时，所有这些操纵子都与plnABCD协同高度激活。其中两个操纵子（分别称为plnEFI和plnJKLR）各自包含一个基因对（分别为plnEF和plnJK），编码两种带有双甘氨酸型前导肽的小阳离子类细菌素肽。编码类细菌素肽的开放阅读框（ORF）之后分别是编码类似于细菌素免疫蛋白的阳离子疏水蛋白的ORF（分别为plnI和-L）。在第三个操纵子（称为plnMNOP）上，也鉴定出了一个类似的类细菌素ORF（plnN）和一个推定的免疫ORF（plnM或-P）。这些发现表明，两种双肽型细菌素（成熟的PlnEF和PlnJK）和一种单肽型细菌素（成熟的PlnN）可能是观察到的细菌素活性的原因。最后一个操纵子（称为plnGHSTUV）包含两个ORF（plnGH），显然分别编码一个ABC转运蛋白及其辅助蛋白，已知它们参与具有前体双甘氨酸型前导肽的肽的加工和输出。确定了启动子结构。在所有五个植物乳杆菌素A诱导操纵子的启动子区域中鉴定出一个包含两个直接重复序列的保守调控样框。这些重复序列可能作为基因表达的调控元件。
