Bacterial Extracellular Polysaccharides in Biofilm Formation and Function.
Bacterial Extracellular Polysaccharides in Biofilm Formation and Function.
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DOI：
10.1128/microbiolspec.mb-0011-2014
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发表时间：
2015-06
影响因子：
3.7
通讯作者：
Wozniak DJ
中科院分区：
文献类型：
--
作者：
Limoli DH;Jones CJ;Wozniak DJ
微生物产生由蛋白质、细胞外 DNA 和多糖组成的生物膜基质，它是细菌群落形成中不可或缺的一部分。对多糖的历史研究表明，它们的过量生产常常会改变菌落形态，并且可以在识别某些物种时起到诊断作用。基质的多糖成分可以为生物膜中的细胞提供许多不同的益处，包括粘附、保护和结构。聚集的多糖充当分子胶，使细菌细胞能够相互粘附以及表面粘附。粘附力使细菌能够抵抗流体运动所施加的物理压力，从而使细胞与营养源分离，从而促进生物和非生物表面的定植。多糖还可以提供针对多种应激的保护，例如干燥、免疫效应物和吞噬细胞和变形虫等捕食者。最后，多糖可以为生物膜提供结构，使细菌群落分层并建立营养物和废物的梯度。通过建立异质种群，准备承受许多细菌遇到的快速变化的环境所产生的压力，这对细菌来说是有利的。多糖结构、性质和作用的多样性凸显了这种基质成分对于细菌成功适应几乎每个生态位的重要性。在这里，我们概述了有关多糖生产为生物膜内细菌群落提供的多样性和益处的当前知识。
Microbes produce a biofilm matrix consisting of proteins, extracellular DNA, and polysaccharides that is integral in the formation of bacterial communities. Historical studies of polysaccharides revealed that their overproduction often alters the colony morphology and can be diagnostic in identifying certain species. The polysaccharide component of the matrix can provide many diverse benefits to the cells in the biofilm, including adhesion, protection, and structure. Aggregative polysaccharides act as molecular glue, allowing the bacterial cells to adhere to each other as well as surfaces. Adhesion facilitates the colonization of both biotic and abiotic surfaces by allowing the bacteria to resist physical stresses imposed by fluid movement that could separate the cells from a nutrient source. Polysaccharides can also provide protection from a wide range of stresses, such as desiccation, immune effectors, and predators such as phagocytic cells and amoebae. Finally, polysaccharides can provide structure to biofilms, allowing stratification of the bacterial community and establishing gradients of nutrients and waste products. This can be advantageous for the bacteria by establishing a heterogeneous population that is prepared to endure stresses created by the rapidly changing environments that many bacteria encounter. The diverse range of polysaccharide structures, properties, and roles highlight the importance of this matrix constituent to the successful adaptation of bacteria to nearly every niche. Here, we present an overview of the current knowledge regarding the diversity and benefits that polysaccharide production provides to bacterial communities within biofilms.