CAREER: Role of Surface Properties in Motility of Bacteria to Control Biofilms

ID：MPS/DMR/BMAT（7623）1151133 PI：Conrad，Jacinta ORG：University of Houston休斯顿大学职业：表面特性在细菌运动性中的作用，以控制生物膜智力优势：该项目的目标是量化表面特性如何影响细菌的运动性，具有高的空间和时间分辨率。 运动性是表面相关细菌生物膜形成的关键因素。 一旦生物膜形成，它们就很难去除，导致数十亿美元的石油和水管道，生物医学植入物和食品损失。 降低这些成本需要新的策略来防止细菌形成生物膜。 在生物膜形成的初始阶段，细菌会改变其运动机制，使其能够不可逆转地附着在附近的表面。 为了验证细菌与表面相互作用对细菌运动特性和附着与脱离速率的影响这一假说，本研究的具体目标是：（1）通过测量细菌在表面上运动的速度和持续性，阐明表面化学性质和弹性对细菌扩散的影响。 单细菌跟踪算法将用于跟踪数千个在表面上移动的细菌，这些表面具有受控的表面电荷和弹性模量，这些表面电荷和弹性模量使用逐层沉积进行设计，从而优化表面特性，以最大限度地减少分散。 (2)量化对表面模式的定向持久性。 均方位移，平均速度，持续时间，和梯度表面上的特征尺寸为1-100微米的细菌的运动角度将使用趋化性模型进行分析，产生关于表面图案如何指导细菌运动的基本数据。 (3)通过测量单个细菌的附着和脱离速率，开发评价微生物表面的测定方法。 这些速率将与两种类型的表面上的所得生物膜的结构相关，所述两种类型的表面具有已证明的生物降解功效，即两亲性聚合物膜和分层褶皱表面。 通过对表面特性对运动性、粘附性和生物膜形成的影响产生新的基本认识，该项目旨在实现涂层的合理设计，以抑制细菌定植，从而阻止生物膜形成。优化的防腐涂层将有助于减少每年数十亿美元的水和资源管道的生物腐蚀损害，以及与医院相关的费用。获得性感染 更广泛地说，近表面运动的详细显微镜调查将对细菌与它们移动的表面之间的相互作用产生新的见解，从而能够对感染和病理学以及细菌表面特性进行定性的新研究。 这项工作产生的信息丰富的数据将改善现有的模型，定向运动和细菌粘附。 最后，这些技术可以应用于将细菌附着和结垢与广泛的物种和表面的表面性质相关联。 拟议的研究将与教育和推广工作相结合，旨在增加休斯顿工程服务不足人群的参与。 首先，将与两所少数民族服务的当地高中（KIPP-休斯顿和DeBakey）合作开发激励学生学习工程的生物污垢培训和学习活动，利用PI与NSF-RET和UH GRADE Camp计划正在进行的工作，将预科妇女引入工程。 其次，PI将继续通过UH和NSF-REU指导本科生进行研究。 最后，两名研究生将在表面的研究指导，和生物工程的跨学科研讨会将由PI发起。 拟议的教学和推广工作将扩大整个休斯顿不同人口的工程参与，反映在非裔美国人和拉丁美洲人（95%和56%）和低收入（80%和49%）学生的高比例分别在KIPP-休斯顿和DeBakey。 同样，PI将在休斯顿大学（13%的非洲裔美国人和21%的拉丁美洲人）开展这些活动，这是美国第二大最多样化的研究型大学。 这项研究的结果将由PI和她的学生在科学文献以及石油和生物医学行业中广泛传播，利用PI作为工业赞助的博士后研究员的经验以及她在德克萨斯州医学中心的持续合作。

ID: MPS/DMR/BMAT(7623) 1151133 PI: Conrad, Jacinta ORG: University of HoustonTitle: CAREER: Role of Surface Properties in Motility of Bacteria to Control BiofilmsINTELLECTUAL MERIT: The objective of this project is to quantify how surface properties influence the motility of bacteria, with high spatial and temporal resolution. Motility is a critical factor in the formation of surface-associated bacterial biofilms. Once biofilms form, they are notoriously difficult to remove, resulting in billions of dollars of damage to oil and water pipelines, biomedical implants, and food. Reducing these costs requires new strategies to prevent bacteria from forming biofilms. In the initial stage of biofilm formation, bacteria modify their motility mechanisms to enable irreversible attachment to nearby surfaces. To test the hypothesis that motility characteristics and rates of bacterial attachment and detachment are affected by the interactions between bacteria and surfaces, the specific aims are: (1) To elucidate the effects of surface chemistry and elasticity on dispersal by measuring velocity and persistence of motion on surfaces. Single-bacterium tracking algorithms will be used to track thousands of bacteria moving on surfaces with controlled surface charge and elastic modulus engineered using layer-by-layer deposition, yielding optimized surface properties to minimize dispersal. (2) To quantify directional persistence in response to surface patterns. The mean-square displacement, mean speed, persistence time, and angle of motion of bacteria on gradient surfaces with feature sizes of 1-100 microns will be analyzed using models for chemotaxis, yielding fundamental data on how surface patterns direct motion in bacteria. (3) To develop assays to evaluate antifouling surfaces by measuring attachment and detachment rates of individual bacteria. These rates will be correlated to the structure of the resultant biofilms on two types of surfaces with demonstrated antifouling efficacy, amphiphilic polymer films and hierarchically wrinkled surfaces. By generating new fundamental understanding of the effects of surface properties on motility, adhesion, and biofilm formation, this project aims to enable the rational design of coatings that inhibit colonization by bacteria and thereby impede biofilm formation.BROADER IMPACTS: Optimized antifouling coatings will help to reduce the billions of dollars in biocorrosion damage in water and resource pipelines each year and in costs related to hospital-acquired infections. More broadly, detailed microscopic investigations of near-surface motility will yield new insights on the interactions between bacteria and the surfaces on which they move, enabling qualitatively new studies of infection and pathology as well as antifouling surface properties. The information-rich data generated by this work will improve existing models for directed motility and for bacterial adhesion. Finally, these techniques can be applied to correlate bacterial attachment and fouling to surface properties across a wide range of species and surfaces. The proposed research will be integrated with educational and outreach efforts aimed at increasing the participation of underserved populations in engineering in Houston. First, training and learning activities on biofouling that inspire students to study engineering will be developed in collaboration with two minority-serving local high schools (KIPP-Houston and DeBakey), leveraging the PI's ongoing work with NSF-RET and the UH GRADE Camp program for introducing precollege women to engineering. Second, the PI will continue to mentor undergraduate students in research through UH and NSF-REU. Finally, two graduate students will be mentored in research on antifouling surfaces, and interdisciplinary workshops on engineering for biology will be initiated by the PI. The proposed teaching and outreach efforts will broaden participation in engineering throughout the diverse population of Houston, reflected by the high proportions of African American and Latino (95% and 56%) and low income (80% and 49%) students at KIPP-Houston and DeBakey, respectively. Likewise, the PI will pursue these activities at the University of Houston (13% African American and 21% Latino), the second most diverse research university in the US. The results from this study will be widely disseminated by the PI and her students in both the scientific literature and to the petroleum and biomedical industries, leveraging the PI's experience as an industrially sponsored postdoctoral researcher and her ongoing collaborations at the Texas Medical Center.