RII Track-4:NSF Engineering mixed microbial communities & bioreactor configurations to optimize biotransformation processes for metal and metalloid bioremediation and biorecove

农业径流和采矿等工业产生的废水通常含有金属和类金属(M&Amp；M)等污染物，它们可能是有毒的，对环境和健康构成威胁。从废水中去除和回收M&AMM对于防止环境污染和发展更可持续的资源利用至关重要。该项目提议利用微生物的能力，将有毒和水溶性的M&Amp；M转化为可作为增值产品回收的无毒形式(例如，可具有多种用途的金属纳米颗粒)。在“一起更好”的理念下，我们计划使用真菌和细菌的混合微生物群落(相对未被探索的群落)来开发用于金属和类金属生物转化过程的生物反应器系统；通过增加微生物群落中合作伙伴的数量和多样性，我们可以创建更具弹性、更宽容和更稳定的社区，与单独的对应社区相比，我们可以改善生物转化过程。拟议的工作将(I)提供关于混合微生物群落中真菌和细菌之间的微生物相互作用的关键基础知识，这是更好地了解自然界中的微生物系统的一个感兴趣的专题；(Ii)为开发从废流中去除和回收有害M&M的改进系统奠定基础，该系统具有变革潜力，可以彻底改变生物修复技术和未来的生物制造。该项目设想使用多领域混合微生物群落(MMC)，特别是相对未被探索的真菌-细菌生物膜，以改进废物中金属和类金属(M&AMP；M)的生物转化和生物修复，并对有益于社会的增值产品(例如，金属纳米颗粒)进行生物回收。该项目将解决使用MMCs进行生物处理的一些主要挑战：对MMCs的了解不足，以及缺乏成功培养MMCs和维持稳定的生物处理的生物反应器。因此，该项目的目标是开发和优化MMC和生物反应器系统，以改进M&Amm；M的生物处理，以进行生物修复和生物回收。作为概念的证明，将以硒(一种在酸性矿山废水中发现的常见金属)为例，评估拟议的真菌-细菌生物膜系统在本项目中用于M&Amp；M生物修复和生物回收的潜在用途。提出了三项主要工作：(1)结合磁钳、剪切流变仪和光学相干断层扫描等前沿技术，建立与环境微生物相关的真菌-细菌生物膜，并表征其结构和力学性能；(2)开发膜生物膜反应器(MBfR)，这是一种基于膜向生长在膜上的生物膜传输气体的紧急技术，以支持真菌-细菌生物膜的建立；(3)评估和优化带有真菌-细菌生物膜的MBfR的性能和稳定性，以去除和回收Se。了解和控制MMCs中的微生物相互作用并开发改进的多域生物反应器系统，对于构建可持续的未来、最大限度地减少污染和利用废流回收高价值产品的产生至关重要。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。

Waste streams from agricultural run-off and industries such as mining typically contain pollutants like metals and metalloids (M&M), which can be toxic and pose a threat to the environment and health. The removal and recovery of M&M from wastewater is crucial to prevent environmental contamination and to develop a more sustainable use of resources. This project proposes to exploit the ability of microbes to transform toxic and water-soluble forms of M&M into non-toxic forms which can be recovered as value-added products (e.g., metallic nanoparticles that can have multiple applications). Under the concept of "together is better", we plan to use mixed microbial communities of fungi and bacteria (relatively unexplored communities) to develop bioreactor systems for metal- and metalloid- biotransformation processes; by increasing the number and diversity of partners in a microbial community we can create more resilient, tolerant, and stable communities with improved biotransformation processes compared to their individual counterparts. The proposed work will (i) provide key fundamental knowledge regarding microbial interactions between fungi and bacteria in mixed microbial communities, a topic of interest to better understand the microbial system in nature; and (ii) lay down the foundation for the development of improved systems for the removal and recovery of harmful M&M from waste streams, which has transformative potential and can revolutionize both bioremediation technologies and future biomanufacturing. This project envisions using multi-domain mixed microbial communities (MMCs), specifically the relatively unexplored fungal-bacterial biofilms, for improved biotransformation and bioremediation of metals and metalloids (M&M) from waste streams and biorecovery of value-added products (e.g., metallic nanoparticles) beneficial to society. This project will address some of the main challenges in using MMCs for bioprocessing: the poor understanding of MMCs and the lack of bioreactors to successfully cultivate MMCs and maintain stable bioprocessing. Thus, the goal of this project is to develop and optimize MMCs and bioreactor systems for improved bioprocessing of M&M for bioremediation and biorecovery. As a proof of concept, selenium (Se, a common metalloid found in acid mine drainage) will be used as an example to assess the potential use of the proposed fungal-bacterial biofilm systems for M&M bioremediation and biorecovery in this project. Three main tasks are proposed: (1) establishing fungal-bacterial biofilms with relevant environmental microorganisms and characterizing their structural and mechanical properties using a combination of cutting-edge techniques including magnetic tweezers, shear rheometry, and optical coherence tomography; (2) developing Membrane Biofilm Reactors (MBfR), an emergent technology based on the use of membranes that transfer gas to a biofilm growing on the membrane, to support fungal-bacterial biofilm establishment; and (3) assessing and optimizing reactor performance and stability of MBfRs with fungal-bacterial biofilms for the removal of Se and its recovery. Understanding and controlling microbial interactions in MMCs and developing improved multi-domain bioreactor systems is key to building a sustainable future minimizing pollution and to utilizing waste streams for the recovery of the generation of high-value products.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.