Dipartimento di Biotecnologie, LAMMB, Policlinico Le Scotte (lotto 5 piano 1), Universita di Siena, 53100 Siena, Italy.
BMC Microbiol. 2011 Apr 14;11:75. doi: 10.1186/1471-2180-11-75.
Different models for biofilm in Streptococcus pneumoniae have been described in literature. To permit comparison of experimental data, we characterised the impact of the pneumococcal quorum-sensing competence system on biofilm formation in three models. For this scope, we used two microtiter and one continuous culture biofilm system.
In both microtiter models the competence system influences stability and structure of biofilm in the late attachment phase and synthetic competence stimulating peptide (CSP) restored wild type phenotypes in the comC mutants unable to produce the peptide. Early attachment of single cells to well bottoms was found for both systems to be competence independent, while later phases, including microcolony formation correlated to an intact competence system. The continuous culture biofilm model was not affected by mutations in the competence locus, but deletion of capsule had a significant impact in this model.
Since biofilm remains a largely uncharacterised multi-parameter phenotype it appears to be advisable to exploit more than one model in order to draw conclusion of possible relevance of specific genotypes on pneumococcal physiology.
文献中已经描述了不同的肺炎链球菌生物膜模型。为了能够比较实验数据，我们在三种模型中研究了肺炎球菌群体感应能力系统对生物膜形成的影响。为此，我们使用了两种微量滴定和一种连续培养生物膜系统。
在这两种微量滴定模型中，群体感应能力系统都会影响到附着后期生物膜的稳定性和结构，并且合成的群体感应刺激肽（CSP）能够恢复无法产生肽的 comC 突变体的野生型表型。我们发现，对于这两种系统来说，单细胞的早期附着都与能力无关，而包括微菌落形成在内的后期阶段则与完整的能力系统相关。连续培养生物膜模型不受能力基因座突变的影响，但荚膜缺失对该模型有显著影响。
由于生物膜仍然是一个特征不明确的多参数表型，因此建议使用多种模型来得出特定基因型对肺炎球菌生理学可能具有相关性的结论。
