来自格拉姆阳性结合元件的两个OB折叠蛋白参与放松体组装和DNA处理
Haifa Laroussi1, Robine Maffo-Woulefack1, Julien Cappèle2
1Université de Lorraine, INRAE, DynAMic, F-54000 Nancy, France.
Nucleic acids research
|November 16, 2025
概括
两个OB折叠蛋白,OrfL和OrfM,是Gram阳性细菌中ICESt3的结合转移的必要辅助蛋白. 它们与放松酶形成复合体,有助于DNA处理和转移启动.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 整合性和结合性元素 (ICE) 是细菌进化至关重要的移动遗传元素,通常传播适应性基因,如抗生素耐药性.
- ICEs利用细菌结合进行传播,这一过程是由放松酶在转移的起源处处理DNA所启动的.
- 在格拉姆阳性细菌中的ICESt3/Tn916/ICEBs1 ICE超级家族使用独特的MOBT放松酶,与通常在其他细菌中发现的不同.
研究的目的:
- 为了阐明OrfL和OrfM的作用,两种由ICESt3编码的OB折叠蛋白,在结合转移过程中.
- 描述ICESt3放松体内OrfL和OrfM的结构和功能相互作用.
- 研究OB折叠蛋白在放松体组合和功能中的更广泛影响.
主要方法:
- 进行了细菌结合试验,以评估ORFL和ORFM对于ICESt3转移的必要性.
- 核磁共振 (NMR) 光谱法用于确定OrfM的3D结构.
- 细菌腺酸环酶双混合 (BACTH) 试验被用于研究蛋白质与蛋白质之间的相互作用.
主要成果:
- OrfL和OrfM形成一个功能复合体,并充当ICESt3结合转移的必要辅助蛋白.
- OrfM的NMR结构揭示了一个OB折叠蛋白质,具有内在灵活的区域.
- OrfL与ICESt3放松酶 (RelSt3) 和宿主PcrA旋酶均表现出相互作用,这表明它具有网络作用.
结论:
- OB折叠蛋白,OrfL和OrfM,是ICESt3放松体的关键组成部分,对于其结合转移至关重要.
- 这些发现突出了涉及OB折叠蛋白的放松酶组装的新机制,与其他细菌系统中发现的更常见的带状螺旋螺旋蛋白形成鲜明对比.
- 在传输过程中,OrfL的交互网络强调了ICE与宿主细胞机械的集成.
相关概念视频
Mechanism of Conjugation
764
Bacterial conjugation is a mechanism of horizontal gene transfer that enables the exchange of genetic material between bacterial cells through direct contact. This process is facilitated by a donor cell carrying a conjugative plasmid, which encodes genes necessary for pilus formation, DNA replication, and transfer. The conjugative plasmid plays a central role in initiating and executing the transfer of genetic material.The tra region of the conjugative plasmid encodes proteins responsible for...
764
The Replisome
38.0K
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
38.0K
The Replisome
9.6K
9.6K
Coordination of Gene Expression Processes in Bacteria
557
The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...
557
Cytoskeletal Proteins in Bacteria
4.1K
Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
4.1K
Protein Complex Assembly
16.6K
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types. Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Many viruses self-assemble into a fully functional unit using the infected host cell to...
16.6K


