A Novel Biomechanical Model of Bacterial Adhesion and Aggregation

该奖项的研究目标是获得一个基本的生物力学模型，能够预测和提高水过滤和生物修复的效率。 方法如下。能源部确定的微生物菌株将在离子浓度与受污染水道相匹配的水环境中培养。使用原子力显微镜的微观表征将确定表面电位，表面间力，粘附能，单细胞的弹性模量，表面粗糙度和沙粒的zeta电位等宏观表征使用标准填充柱测试将测量不同水流量和温度的过滤效率。 这些信息将被输入到一个新的模型的粘附分离的细胞，液-固相互作用，并统计保留细胞在砂基板。基于快速的单细胞表征，最终可以预测和测试无数细菌菌株的宏观过滤行为。如果成功的话，这项研究的好处将包括：（i）预测多孔介质中微生物的命运和运输行为，（ii）原位或增强地下生物修复和生物强化的设计，评估和可行性研究，（iii）有效实施工程（砂滤器）或天然（iv）病原体在饮用水供应中的迁移和微生物强化采油。 从长远来看，研究结果将有助于解决世纪随着世界人口增长和全球气候变化而日益增长的对清洁饮用水的需求。

The research objective of this award is to derive a fundamental biomechanical model capable of predicting and improving efficiency of water filtration and bioremediation. The approach is as follows. Microbial strains identified by the Department of Energy will be cultured in aqueous environment with ionic concentration matching that of the polluted waterways. Micro-characterization using atomic force microscopy will determine surface potential, intersurface forces, adhesion energy, and elastic modulus of single cells, surface roughness and zeta potential of sand grains etc. Macro-characterization using standard packed column tests will measure filtration efficiency for different water flow rates and temperature. Such information will be fed into a new model of adhesion-detachment of cells, liquid-solid interaction, and statistical retention of cells on sand substrates. Based on quick single cell characterization, macroscopic filtration behavior of a myriad of bacterial strains can ultimately be predicted and tested. If successful, the benefits of this research will include (i) prediction of fate and transport behavior of microorganisms in porous media, (ii) design, evaluation and feasibility studies of in-situ or enhanced subsurface bioremediation and bioaugmentation, (iii) effective implementation of engineered (sand filters) or natural (bank filtration) filtrations processes for water treatments, (iv) migration of pathogens in drinking water supplies and microbial enhanced oil recovery. The research results will in a long run contribute to resolving the increasing need for clean drinking water in the 21st century with growing world population and drastic global climate change.