Surface-associated motility of Acinetobacter baumannii and its epigenetic control via AamA-specific DNA methylation

鲍曼不动杆菌的表面相关运动及其通过 Aama 特异性 DNA 甲基化的表观遗传控制

• 批准号: 258354423
• 负责人: Privatdozent Dr. Gottfried Wilharm
• 金额: --
• 依托单位: Projektgruppe 2: Acinetobacter baumannii - Biologie eines Krankenhauserregers
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/258354423?language=en
• 关键词: Surface; associated; motility; Acinetobacter; baumannii

Surface-associated motility is widespread among clinical isolates of Acinetobacter baumannii and considered to contribute to virulence and persistence in the hospital environment. During the previous funding period we characterized a set of more than 30 motility-deficient mutants with respect to motility, growth, biofilm formation, antibiotic resistance and virulence in the Galleria mellonella infection model. Overall, our studies highlight the interrelatedness of motility, biofilm and virulence properties. Of particular interest, we identified sulfite reductase activity as a crucial factor of biofilm formation, virulence and antibiotic resistance suggesting a role of H2S as a signaling molecule. Moreover, we identified a novel DNA adenine methyltransferase which we functionally characterized and which we termed AamA. For the first time, we investigated the DNA methylome of an A. baumannii strain using single-molecule real time sequencing and our results suggest an AamA-dependent regulon involved in motility and responding to different environmental conditions. Our model is that of an epigenetic control of gene expression via transient DNA methylation mediated by AamA. To scrutinize our hypotheses, we would like to continue to define the AamA-dependent methylome in response to different environmental conditions including motility, biofilm formation, osmotic and antibiotic stress. RT-PCR and RNA sequencing will be applied to define the responses and correlate them with specific methylation patterns. To complement our understanding of the AamA regulon we intend to exploit proteomics approaches to identify AamA interaction partners and to study their influence on DNA methylation. In this way, we expect to contribute to understanding of adaptation processes of this pathogen.

表面相关运动性在鲍曼不动杆菌临床分离株中广泛存在，并被认为有助于在医院环境中的毒力和持久性。在上一个资助期间，我们在大蜡螟感染模型中描述了一组30多个运动缺陷突变体的运动性、生长、生物膜形成、抗生素耐药性和毒力。总的来说，我们的研究突出了运动性，生物膜和毒力特性的相互关系。特别感兴趣的是，我们确定了亚硫酸盐还原酶活性作为生物膜形成，毒力和抗生素抗性的关键因素，这表明H2S作为信号分子的作用。此外，我们确定了一种新的DNA腺嘌呤甲基转移酶，我们的功能特点，我们称之为AamA。我们首次研究了A.我们的结果表明，AamA依赖性调节子参与运动和响应不同的环境条件。我们的模型是通过AamA介导的瞬时DNA甲基化对基因表达的表观遗传控制。为了仔细检查我们的假设，我们希望继续定义AamA依赖性甲基化组以响应不同的环境条件，包括运动性、生物膜形成、渗透压和抗生素应激。将应用RT-PCR和RNA测序来定义反应并将它们与特定的甲基化模式相关联。为了补充我们对AamA调节子的理解，我们打算利用蛋白质组学方法来识别AamA相互作用伙伴，并研究它们对DNA甲基化的影响。通过这种方式，我们希望有助于了解这种病原体的适应过程。