title: Escherichia coli toxin gene hipA affects biofilm formation and DNA release.
abstract: Toxin-antitoxin (TA) systems in Escherichia coli may play a role in biofilm formation, but the mechanism involved remains debatable. It is not known whether the TA systems are responsible for extracellular DNA (eDNA) in biofilms. In this study, we investigated the function of the hipBA TA system in biofilm formation by Escherichia coli strain BW25113. First, the deletion of the HipBA TA system in E. coli BW25113 significantly reduced the biofilm biomass without antibiotic stress. Second, treatment of the BW25113 biofilm with DNase I caused a major reduction in biofilm formation, whereas similar treatment of the hipA mutant biofilm had only a minor effect. Third, the inactivation of HipA reduced the level of eDNA present in biofilm formation, and addition of BW25113 genomic DNA stimulated biofilm formation for both the wild-type and hipA mutant. Fourth, the wild-type cells underwent significantly more cell lysis than the hipA mutant. These results suggest that hipA plays a significant role during biofilm development and that eDNA is an important structural component of E. coli BW25113 biofilms. Thus, the TA system may enhance biofilm formation through DNA release.
authors: State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Junqiao
authors: J
authors: Zhao
authors: National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Qian
authors: Q
authors: Wang
authors: State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Mingji
authors: M
authors: Li
authors: School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors: Björn D
authors: BD
authors: Heijstra
authors: State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Shengjun
authors: S
authors: Wang
authors: National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.|State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Quanfeng
authors: Q
authors: Liang
authors: National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.|State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Jinan 250100, PR China.
authors: Qingsheng
authors: Q
authors: Qi
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D004269:DNA, Bacterial / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion
chemical_list: D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C070741:hipA protein, E coli