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

来自农业径流和采矿等工业的废物流通常含有金属和类金属（MM）等污染物，这些污染物可能有毒并对环境和健康构成威胁。从废水中去除和回收M M对于防止环境污染和开发更可持续的资源利用至关重要。该项目建议利用微生物将有毒和水溶性形式的MM转化为无毒形式的能力，这些形式可以作为增值产品回收（例如，可以具有多种应用的金属纳米颗粒）。在“一起更好”的概念下，我们计划使用真菌和细菌的混合微生物群落（相对未开发的群落）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，耐受性和稳定的群落，与其单独的对应物相比，生物转化过程得到改善。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微生物相互作用的关键基础知识，这是一个感兴趣的话题，以更好地了解自然界中的微生物系统;（ii）为开发改进的系统奠定基础，用于从废物流中去除和回收有害的M M，这具有变革潜力，可以彻底改变生物修复技术和未来的生物制造。该项目设想使用多域混合微生物群落（MMC），特别是相对未开发的真菌-细菌生物膜，用于改善废物流中金属和类金属（MM）的生物转化和生物修复以及增值产品（例如，金属纳米颗粒）有益于社会。该项目将解决使用MMC进行生物加工的一些主要挑战：对MMC的了解不足以及缺乏成功培养MMC和维持稳定生物加工的生物反应器。因此，本项目的目标是开发和优化金属基复合材料和生物反应器系统，以改善生物处理的生物修复和生物回收的M M。作为一个概念的证明，硒（硒，一种常见的金属中发现的酸性矿山排水）将被用作一个例子，以评估潜在的使用建议的真菌-细菌生物膜系统的M M生物修复和生物恢复在这个项目中。提出了三项主要任务：（1）利用相关环境微生物建立真菌-细菌生物膜，并使用包括磁镊、剪切流变学和光学相干断层扫描在内的尖端技术的组合来表征其结构和机械性质;（2）开发膜生物膜反应器（MBfR），这是一种基于使用膜的新兴技术，该膜将气体转移到生长在膜上的生物膜，以支持真菌-细菌生物膜的建立;和（3）评估和优化具有真菌-细菌生物膜的MBfR的反应器性能和稳定性，以去除Se并回收Se。了解和控制MMC中的微生物相互作用以及开发改进的多域生物反应器系统是建立可持续未来的关键，最大限度地减少污染，并利用废物流回收生产高价值产品。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值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.