Department of Microbial Infection and Immunity, Department of Microbiology, Center for Microbial Interface Biology, The Ohio State University Medical Center, Columbus, OH 43210, USA.
FEMS Microbiol Rev. 2012 Jul;36(4):893-916. doi: 10.1111/j.1574-6976.2011.00322.x. Epub 2012 Jan 23.
Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure-function relationships, regulation, and the role of individual matrix molecules in niche biology.
生物膜是细菌在环境和临床中主要的生长形式。生物膜的形成关键在于黏附、增殖和分散阶段。这些阶段都包括细胞外基质的加强或调节。铜绿假单胞菌一直是生物膜形成研究的模式生物。此外，其他假单胞菌在植物定殖和环境持久性过程中也利用生物膜形成。假单胞菌产生几种生物膜基质分子，包括多糖、核酸和蛋白质。辅助生物膜形成和适应不同条件的附加基质成分也由假单胞菌产生。生物膜形成带来的适应性使具有独特和可区分的菌落形态的遗传变异体得以选择。例如，粗糙小菌落变异体和褶皱扩散体（WS）分别过度产生 Psl/Pel 或纤维素，以及过度产生藻酸盐的粘液菌。这些变异体的大量出现表明，假单胞菌利用基质形成亚群为整个群体提供特定的益处。这篇综述将重点介绍各种多糖以及其他假单胞菌生物膜基质成分。讨论将集中在结构-功能关系、调控以及单个基质分子在生态位生物学中的作用。
