Contribution of Autolysin and Sortase A during Enterococcus faecalis DNA-Dependent Biofilm Development
Contribution of Autolysin and Sortase A during Enterococcus faecalis DNA-Dependent Biofilm Development
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DOI：
10.1128/iai.00219-09
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发表时间：
2009-09-01
影响因子：
3.1
通讯作者：
Hultgren, Scott J.
中科院分区：
文献类型：
--
作者：
Guiton, Pascale S.;Hung, Chia S.;Hultgren, Scott J.
生物被膜的产生是粪肠球菌临床分离株的主要属性。虽然一些因子，如分选酶、自溶素和细胞外DNA（eDNA），已经与E.虽然这些因素对粪便生物膜产生的影响很大，但这些因素对该过程的作用机制尚未完全阐明。在这项研究中，我们定义的主要E的重要作用。粪球菌自溶素（Atn）、eDNA和分选酶A（SrtA）在静态和流体动力学条件下生物膜形成的发育阶段期间的变化。srtA的缺失影响附着阶段并导致生物膜产生的缺陷。Atn缺陷型突变体在生物膜发育中由于初级粘附和DNA释放的缺陷而延迟，这在生物膜的成熟和建筑稳定性的累积阶段中是特别重要的。共聚焦激光扫描和冷冻干燥电子显微镜的生物膜生长在流体力学条件下显示，E。粪肠球菌产生DNA酶I敏感的纤维状网络，其对于生物膜稳定性是重要的，并且在atn缺陷型突变生物膜中不存在。本研究建立了SrtA和Atn的阶段特异性要求，并证明了Atn在E.粪便。
Biofilm production is a major attribute of Enterococcus faecalis clinical isolates. Although some factors, such as sortases, autolysin, and extracellular DNA (eDNA), have been associated with E. faecalis biofilm production, the mechanisms underlying the contributions of these factors to this process have not been completely elucidated yet. In this study we define important roles for the major E. faecalis autolysin (Atn), eDNA, and sortase A (SrtA) during the developmental stages of biofilm formation under static and hydrodynamic conditions. Deletion of srtA affects the attachment stage and results in a deficiency in biofilm production. Atn-deficient mutants are delayed in biofilm development due to defects in primary adherence and DNA release, which we show to be particularly important during the accumulative phase for maturation and architectural stability of biofilms. Confocal laser scanning and freeze-dry electron microscopy of biofilms grown under hydrodynamic conditions revealed that E. faecalis produces a DNase I-sensitive fibrous network, which is important for biofilm stability and is absent in atn-deficient mutant biofilms. This study establishes the stage-specific requirements for SrtA and Atn and demonstrates a role for Atn in the pathway leading to DNA release during biofilm development in E. faecalis.