SemiSynBio-III: Precision assembly and electronic properties of protein nanowire circuits using DNA origami

微电子制造严重依赖于使用硅衬底和大量掩模/分层步骤，这些步骤带来了严重的缺点，如极端的进入成本、高能源消耗以及几乎达到的可扩展性和器件几何尺寸的有限限制，从而在能够有效解决这些问题的技术上造成了缺口。开发下一代电子器件需要新材料、可持续的制造工艺和新颖的电路拓扑。这项研究将开发使用细菌菌毛的工程蛋白质纳米线，通过精确设计和组装由DNA组成的结构支架来导电，这种结构支架被称为DNA折纸。纳米线之间的相互作用及其环境可以用单分子技术和为薄层组装结构开发的电子方法来读出，以在分子尺度上表征导电性。这些跨学科进展的结合最终将使下一代计算应用的模块化生物电子设备的开发成为可能。这项研究将为参与该项目的交叉培训学生提供跨学科的协作互动和独特的机会，并将通过培训参与研究的每个机构的本科生作为外展努力的“大使”，进一步扩大影响范围。研究生和本科生的综合互动将提供举办K-12参与项目的机会，包括对中学教师的培训。通过跨学校和地区的合作来分享学生、想法和最佳实践，这项研究计划将使学生和公众对生物阳离子电子学的新发现感到兴奋。在自然界中，长距离(10 Nm)的电子传输通常是在富含芳香残基或氧化还原活性基团的组装蛋白质中实现的。从这个角度来看，导电生物纳米线在下一代电子设备中的各种技术应用前景广阔。硫还原地杆菌在很大程度上通过其环境中无机金属氧化物的还原而生存，并通过其IV型菌毛有效地在细胞外传输电子。菌毛的导电性反过来又与芳香氨基酸紧密堆积的核心联系在一起，这有效地允许残基之间的电子跳跃。这项研究将利用蛋白质工程和合成生物学的方法来设计地质杆菌的导电菌毛，以创造出可以通过与配体相互作用和自组装来调节其导电性的蛋白质纳米线。蛋白质纳米线将以纳米级的分辨率组装到DNA折纸上，以创建具有定义的电化学连接的精确结构的电路。单分子电化学表征将允许对基本电路的详细了解，这反过来将导致生物阳极电子组件的基本设计规则的发展。总体而言，这项研究将提供对生物纳米线的结构设计、组装和电子传输机制的更好的理解，包括开发基本的电子部件，如晶体管，并将这些元素构建成有用的设备，如存储器。该项目由生物科学局(BIO)的分子和细胞生物科学部(MCB)、计算机和信息科学与工程局(CESE)的计算和通信基础部(CCF)联合资助。工程局(ENG)的电气、通信和网络系统(ECCS)部门和数学和物理科学局(MPS)的材料研究部(DMR)。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Microelectronics fabrication critically relies on using silicon substrates and numerous masking/layering steps that bring serious drawbacks such as extreme entry costs, high energy consumption, and finite limits on scalability and device geometries that have nearly been reached, creating a gap in technologies able to effectively address these issues. New materials, sustainable fabrication processes, and novel circuit topologies are necessary to develop next-generation electronic devices. This research will develop engineered protein nanowires using bacterial pili that conduct electricity by precisely designing and assembling structural scaffolds made of DNA, known as DNA origami. The interactions of the nanowires with each other and their environments can be read out using single molecule techniques and electronic methods developed for thin layer assembled structures to characterize conductivities at the molecular scale. The combination of these interdisciplinary advances will ultimately enable the development of modular bioelectronic devices for next-generation computing applications. This research will provide interdisciplinary collaborative interactions and unique opportunities for cross-training students participating in this project and will further extend the reach by training undergraduates from each institution involved in the research to serve as ‘Ambassadors’ for outreach efforts. The integrated graduate and undergraduate interactions will provide opportunities to host K-12 participation programs, including training for secondary school teachers. By working across schools and regions to share students, ideas, and best practices, this research program will generate ongoing student and public excitement around new discoveries in bionanoelectronics.In nature, long-range (10 nm) electron transport is often achieved in assembled proteins rich in aromatic residues or redox-active groups. From this view, conductive biological nanowires hold strong promise for a variety of technological applications in next-generation electronic devices. The bacterium Geobacter sulferreducens survives largely through the reduction of inorganic metal-oxides in its environment and efficiently transports electrons extracellularly via its type IV pili. Pili conductivity has, in turn, been linked to a densely packed core of aromatic amino acids that effectively allows electron hopping between residues. This research will engineer the conductive pili of Geobacter using protein engineering and synthetic biology methods to create protein nanowires whose conductivity can be modulated through interactions with ligands and self-assembly. The protein nanowires will, in turn, be assembled onto DNA origami at a nanoscale resolution to create precisely structured circuits with defined electrochemical junctions. Single-molecule electrochemical characterization will allow for a detailed understanding of the underlying circuitry, which will, in turn, lead to the development of basic design rules for bionanoelectronic assemblies. Overall, this research will provide an improved understanding of structural design, assembly, and electron transport mechanisms in biological nanowires, including developing fundamental electronic parts, such as transistors, and building these elements into useful devices such as memory.The project was jointly funded by the Division of Molecular and Cellular Biosciences (MCB) in the Directorate for Biological Sciences (BIO); Division of Computing and Communication Foundations (CCF) in the Directorate for Computer and Information Science and Engineering (CISE); Division of Electrical, Communications and Cyber Systems (ECCS) in the Directorate for Engineering (ENG) and the Division of Materials Research (DMR) in the Directorate for Mathematical and Physical Sciences (MPS).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.