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细菌表面的海明结合DNA结构促进细胞外电子转移

Obinna M Ajunwa^1,2, Gabriel Antonio S Minero¹, Sissel D Jensen¹

¹Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark.

Nucleic acids research

|August 22, 2025

概括

在细菌生物膜中,G-四重复 (G4) DNA和血红蛋白形成了使细胞外电子转移 (EET) 成为可能的复合体. 这些G4-DNA/血红素复合体作为电导体,促进细菌的能量保存和防御机制.

科学领域:

微生物学
生物化学
生物电化学

背景情况:

细菌生物膜中的非正规DNA结构具有未知的功能.
细胞外电子转移 (EET) 对于细菌的生存和能量保存至关重要,特别是在氧气限制下.

研究的目的:

研究细菌细胞外电子转移 (EET) 中G四重复 (G4) DNA结构的作用.
阐明G4-DNA/血红蛋白复合体在生物膜中促进EET的机制.

主要方法:

作为一个模型生物体使用了 Staphylococcus.
研究了EET需要的细胞外DNA和血红蛋白.
使用电极分析了与表面相关的G4-DNA/hemin复合物的电子转移能力.
描述了G4-DNA/hemin复合体的过氧酶类DNA酶活性.

主要成果:

在S. epidermidis生物膜中,细胞外DNA和血红蛋白对EET至关重要.
在无氧条件下,与表面相关的G4-DNA/hemin复合体促进了从细菌到电极的电子转移.
G4-DNA/血红素复合体作为稳定的电导体,使得长时间的EET成为可能.
G4-DNA/hemin复合体表现出类似过氧化酶的DNA酶活性,将电子转移到H2O2.

结论:

在细菌细胞外电子转移 (EET) 中,G-四重复的DNA结构具有关键作用.
这些G4-DNA/hemin复合体作为生物膜中的强大的电导体,支持细菌的能量储存.
这些发现揭示了非正规DNA在细菌新陈代谢中的新功能和氧化应激防御中的潜在作用.

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