BcsQ is an essential component of the Escherichia coli cellulose biosynthesis apparatus that localizes at the bacterial cell pole
BcsQ is an essential component of the Escherichia coli cellulose biosynthesis apparatus that localizes at the bacterial cell pole
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DOI：
10.1111/j.1365-2958.2009.06678.x
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发表时间：
2009-05-01
影响因子：
3.6
通讯作者：
Ghigo, Jean-Marc
中科院分区：
文献类型：
--
作者：
Le Quere, Benjamin;Ghigo, Jean-Marc
生物膜是一种微生物群落，其特征是单个细胞能够相互粘连并产生细胞外基质，从而确保生物膜的物理凝聚力，从而实现三维生长。许多细菌产生纤维素作为生物膜基质聚合物，这一性质依赖于细菌纤维素合成(BCS)蛋白的表达及其与二鸟苷环酶产生的环状二鸟苷一磷酸第二信使(c-di-GMP)结合时的翻译后激活。在大肠杆菌和其他肠杆菌科细菌中，两个未知功能的基因yhjR和yhjQ位于BCS基因的上游。在这里，我们证明了yhjQ，而不是yhjR，是纤维素生物合成所必需的；因此它被重新命名为bcsQ。使用绿色荧光蛋白(GFP)融合的方法，我们证明了BcsQ，一个心灵的同源物，显示了一个极性的定位，细胞对细胞的黏附是通过在BcsQ标记的极点产生纤维素来启动的。虽然我们没有检测到其他BCS蛋白的类似定位，但免疫金标记法在单个细菌的极点对纤维素本身进行了标记，表明了纤维素生物合成装置的局部活性。这些结果表明，BcsQ可能参与了肠杆菌科纤维素生物合成活性的空间限制。
Biofilms are microbial communities characterized by three-dimensional growth resulting from the ability of individual cells to adhere to each other as well as to produce an extracellular matrix that ensures biofilm physical cohesion. Numerous bacteria produce cellulose as a biofilm matrix polymer, a property relying on the expression of bacterial cellulose synthesis (Bcs) proteins and their post-translational activation upon binding of cyclic di-guanosine mono-phosphate second messenger (c-di-GMP) produced by diguanylate cyclases. In Escherichia coli and other Enterobacteriaceae, two genes of unknown function, yhjR and yhjQ, are located upstream of the bcs genes. Here, we show that yhjQ, but not yhjR, is essential for cellulose biosynthesis; it has therefore been renamed bcsQ. Using a green fluorescent protein (GFP) fusion approach, we demonstrate that BcsQ, a MinD homologue, displays a polar localization and that cell-to-cell adhesion is initiated through production of cellulose at the BcsQ-labelled pole. Although we did not detect a similar localization for other Bcs proteins, immunogold labelling of cellulose itself at the pole of individual bacteria indicates the localized activity of the cellulose biosynthesis apparatus. These results therefore suggest that BcsQ could participate in spatial restriction of cellulose biosynthesis activity in Enterobacteriaceae.