A master regulator for biofilm formation by Bacillus subtilis
A master regulator for biofilm formation by Bacillus subtilis
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DOI：
10.1111/j.1365-2958.2004.04440.x
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发表时间：
2005-02-01
影响因子：
3.6
通讯作者：
Losick, R
中科院分区：
文献类型：
--
作者：
Kearns, DB;Chu, F;Losick, R
枯草芽孢杆菌的野生菌株能够形成结构复杂的细胞群落，称为生物膜。对生物膜形成至关重要的是eps操纵子，它被认为负责胞外多糖的生物合成，胞外多糖将细胞链捆绑在一起。我们报道了eps的转录受到SinR的负调控，SinR是一种抑制因子，被发现与操纵子调控区域的多个位点结合。sinR的突变绕过了两个未知功能基因ylbF和ymcA以及sinI在生物膜形成中的要求，而sinI已知编码sinR的拮抗剂。我们认为这些基因是一个通路的成员，负责抵消sinr介导的抑制。我们进一步提出，SinR是控制浮游状态（细菌在液体中以单细胞形式游动或以小群体在表面上游动）和无基状态（细菌相互粘附形成束链并组装成多细胞群落）之间转变的主要调节剂。
Wild strains of Bacillus subtilis are capable of forming architecturally complex communities of cells known as biofilms. Critical to biofilm formation is the eps operon, which is believed to be responsible for the biosynthesis of an exopolysaccharide that binds chains of cells together in bundles. We report that transcription of eps is under the negative regulation of SinR, a repressor that was found to bind to multiple sites in the regulatory region of the operon. Mutations in sinR bypassed the requirement in biofilm formation of two genes of unknown function, ylbF and ymcA, and sinI, which is known to encode an antagonist of SinR. We propose that these genes are members of a pathway that is responsible for counteracting SinR-mediated repression. We further propose that SinR is a master regulator that governs the transition between a planktonic state in which the bacteria swim as single cells in liquid or swarm in small groups over surfaces, and a sessile state in which the bacteria adhere to each other to form bundled chains and assemble into multicellular communities.