Devaraj Aishwarya, Justice Sheryl S, Bakaletz Lauren O, Goodman Steven D
Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, OH, 43205, USA.
Mol Microbiol. 2015 Jun;96(6):1119-35. doi: 10.1111/mmi.12994. Epub 2015 Apr 16.
Most chronic and recurrent bacterial infections involve a biofilm component, the foundation of which is the extracellular polymeric substance (EPS). Extracellular DNA (eDNA) is a conserved and key component of the EPS of pathogenic biofilms. The DNABII protein family includes integration host factor (IHF) and histone-like protein (HU); both are present in the extracellular milieu. We have shown previously that the DNABII proteins are often found in association with eDNA and are critical for the structural integrity of bacterial communities that utilize eDNA as a matrix component. Here, we demonstrate that uropathogenic Escherichia coli (UPEC) strain UTI89 incorporates eDNA within its biofilm matrix and that the DNABII proteins are not only important for biofilm growth, but are limiting; exogenous addition of these proteins promotes biofilm formation that is dependent on eDNA. In addition, we show that both subunits of IHF, yet only one subunit of HU (HupB), are critical for UPEC biofilm development. We discuss the roles of these proteins in context of the UPEC EPS.
大多数慢性和复发性细菌感染都涉及生物膜成分，其基础是细胞外聚合物（EPS）。细胞外DNA（eDNA）是致病性生物膜EPS的一种保守且关键的成分。DNABII蛋白家族包括整合宿主因子（IHF）和组蛋白样蛋白（HU）；二者都存在于细胞外环境中。我们之前已经表明，DNABII蛋白常与eDNA相关联，并且对于将eDNA用作基质成分的细菌群落的结构完整性至关重要。在此，我们证明尿路致病性大肠杆菌（UPEC）菌株UTI89在其生物膜基质中纳入了eDNA，并且DNABII蛋白不仅对生物膜生长很重要，而且具有限制性；外源添加这些蛋白可促进依赖于eDNA的生物膜形成。此外，我们表明IHF的两个亚基，但只有HU的一个亚基（HupB）对UPEC生物膜发育至关重要。我们在UPEC EPS的背景下讨论了这些蛋白的作用。
