Dynamics and control of biofilms of the oligotrophic bacterium Caulobacter crescentus
Dynamics and control of biofilms of the oligotrophic bacterium Caulobacter crescentus
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DOI：
10.1128/jb.186.24.8254-8266.2004
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发表时间：
2004-12-01
影响因子：
3.2
通讯作者：
Spormann, AM
中科院分区：
文献类型：
--
作者：
Entcheva-Dimitrov, P;Spormann, AM
新月柄杆菌是一种寡营养的α-变形菌，具有复杂的细胞周期，包括无柄和有毛、有鞭毛的群细胞。由于 C. crescentus 的自然生活方式本质上涉及表面相关的固着状态，因此我们研究了 C. crescentus 生物膜在流体动力系统中在玻璃表面上发育的动力学和控制。与经过充分研究的铜绿假单胞菌、大肠杆菌和霍乱弧菌的生物膜相比，新月杆菌 CB15 细胞形成双相生物膜，主要由细胞单层生物膜和含有致密蘑菇状结构的生物膜组成。基于 C. crescentus 菌株 CB15 野生型及其固着器 (hfsA; DeltaCCO095)、菌毛 (DeltapilA-cpaF::Omegaaac3)、运动性 (motA)、鞭毛 (flgH) 突变体和缺乏固着器和鞭毛的双突变体 (hfsA; flgH) 之间的比较，提出了 C. crescentus 生物膜形成的模型。对于这两种生物膜形式，有柄细胞尖端的固着结构对于介导初始附着至关重要。通过单极鞭毛的游泳运动增强了初始附着并使子代群细胞能够逃离单层生物膜。鞭毛结构也有助于维持蘑菇结构。 IV 型菌毛增强，但不是初始粘附阶段绝对需要的。然而，菌毛对于形成和维持明确的三维蘑菇状生物膜至关重要。菌毛参与蘑菇结构是新月菌 IV 型菌毛的一个新功能。这些独特的生物膜特征表明，C. crescentus 种群在空间上多样化，形成无柄的“干细胞”样亚群（单层生物膜），其产生的后代细胞能够通过游泳运动探索水性贫营养环境，并且亚群在大型蘑菇结构中积累。
Caulobacter crescentus is an oligotrophic alpha-proteobacterium with a complex cell cycle involving sessile-stalked and piliated, flagellated swarmer cells. Because the natural lifestyle of C. crescentus intrinsically involves a surface-associated, sessile state, we investigated the dynamics and control of C. crescentus biofilms developing on glass surfaces in a hydrodynamic system. In contrast to biofilms of the well-studied Pseudomonas aeruginosa, Escherichia coli, and Vibrio cholerae, C. crescentus CB15 cells form biphasic biofilms, consisting predominantly of a cell monolayer biofilm and a biofilm containing densely packed, mushroom-shaped structures. Based on comparisons between the C. crescentus strain CB15 wild type and its holdfast (hfsA; DeltaCCO095), pili (DeltapilA-cpaF::Omegaaac3), motility (motA), flagellum (flgH) mutants, and a double mutant lacking holdfast and flagellum (hfsA; flgH), a model for biofilm formation in C. crescentus is proposed. For both biofilm forms, the holdfast structure at the tip of a stalked cell is crucial for mediating the initial attachment. Swimming motility by means of the single polar flagellum enhances initial attachment and enables progeny swarmer cells to escape from the monolayer biofilm. The flagellum structure also contributes to maintaining the mushroom structure. Type IV pili enhance but are not absolutely required for the initial adhesion phase. However, pili are essential for forming and maintaining the well-defined three-dimensional mushroom-shaped biofilm. The involvement of pili in mushroom architecture is a novel function for type IV pili in C. crescentus. These unique biofilm features demonstrate a spatial diversification of the C. crescentus population into a sessile, "stem cell"-like subpopulation (monolayer biofilm), which generates progeny cells capable of exploring the aqueous, oligotrophic environment by swimming motility and a subpopulation accumulating in large mushroom structures.