Understanding and using microbial conductive nanowires

项目摘要 电子沿硫还原菌蛋白细丝网络的长距离(10微米)传输，称为 微生物纳米线被用来解释一系列全球重要的氧化还原现象。这个 这些纳米线非凡的电子传导能力引发了人们对 医疗应用空间，如建筑生物兼容材料和生物传感器。十多年来，G. 硫还原菌纳米线被认为是IV型细菌菌毛，由许多间接遗传和 生化观察。最近，我们发现这些导电纳米线不是由IV型菌毛制成的。 相反，这些结构是聚合的多血红素c型细胞色素，如OMCs和OMCE，它 以前从未被描述过。目前，我们对细胞色素附属物的了解还很少。 有限的。这项研究旨在解决呼吸过程中细胞色素细丝的基本科学问题。 并将我们的发现应用于普通医学领域。具体地说，我将：a)确定和 通过生物信息学搜索在细菌和古菌菌株中表征新的细胞色素细丝 然后是微观验证。B)用高分辨率研究这些细丝的传导机制 低温电子显微镜(Cryo-EM)和电导率测量。C)设计自组装导电体 基于结构知识的纳米线。这些结果已经并将继续推动我们对 细胞色素纳米线和自组装纳米线产品可用于许多未来的生物医学 申请。

Project Summary Long-range (>10 µm) transport of electrons along networks of G. sulfurreducens protein filaments, known as microbial nanowires, has been invoked to explain a wide range of globally important redox phenomena. The remarkable electronic conduction capability of those nanowires has sparked a great deal of interest in the medical application space, such as building biocompatible materials and biosensors. For over a decade, G. sulfurreducens nanowires were thought to be bacterial type IV pili, supported by many indirect genetic and biochemical observations. Recently we showed that these conductive nanowires are not made of type IV pilins. Instead, these structures are a polymerized multi-heme c-type cytochrome, such as OmcS and OmcE, which have never been characterized before. Currently, our knowledge of cytochrome appendages is still very limited. This study aims to address fundamental scientific questions about cytochrome filaments in respiring prokaryotes and apply our discoveries to the general medical field. Specifically, I will: A) identify and characterize novel cytochrome filaments in bacterial and archaeal strains through bioinformatics searches followed by microscopic validation. B) Study the conduction mechanism of these filaments by high-resolution cryogenic electron microscopy (cryo-EM) and conductivity measurement. C) Design self-assembled conductive nanowires based on structural knowledge. The results have and will continue to advance our understanding of cytochrome nanowires, and self-assembling nanowire products can be used in many future biomedical applications.