Dispersion of Pseudomonas Aeruginosa Biofilms

纽约州立大学宾厄姆顿分校的David Davies博士获得了一项资助，用于分离、鉴定和表征一种导致铜绿假单胞菌生物膜自身分散的因素。在自然界中，像铜绿假单胞菌这样的细菌通常附着在表面上生长，而不是悬浮在液体中（如试管中的实验室培养肉汤）。表面附着的细菌生长被称为生物膜。提出的工作的目标是表征生物膜的自分散，以开发新的方法来控制细菌生物膜。用溶剂萃取法从废培养基中分离出分散诱导因子，用色谱法纯化，然后进行标准的结构化学分析。该分析将包括用于官能团鉴定的红外光谱，质谱和核磁共振光谱。将对隔离因子进行测试，以确定其在隔离过程的每个阶段作为色散诱导剂的有效性。将使用快速筛选技术将含有诱导剂化合物的分离馏分添加到模拟生物膜中，这些将在连续培养生物膜群体的测试中得到验证。这项工作将包括本科生在学年和夏季学期的研究参与。化学系和生物系的学生培训将包括实验室部分，包括废培养基中因子的光谱识别和分散诱导和非诱导细菌生物膜的抗生素功效测试。感染和工业系统中的微生物生物膜由于对杀微生物剂的耐药性而呈现出显著的问题。这种抗性在很大程度上是由于生物膜中细胞的聚集性。戴维斯博士的实验室发现，从铜绿假单胞菌的高细胞密度培养中回收的无细胞废培养基，当外源添加到生长的生物膜中时，能够诱导生物膜自身分散。这项工作有望为控制铜绿假单胞菌的生物膜形成和持久性提供一种新的方法，并导致在工业、家庭和医疗应用中加强生物膜控制和去除的策略的发展。

A grant has been awarded to Dr. David Davies of the State University of New York at Binghamton to isolate, identify and characterize a factor responsible for inducing autodispersion of Pseudomonas aeruginosa biofilms. In nature, bacteria such as P. aeruginosa often grow attached to surfaces rather than suspended in liquid (such as in a laboratory culture broth in a test tube). Surface-attached bacterial growth is known as a biofilm. The goal of the proposed work is to characterize biofilm autodispersion in order to develop novel methods for the control of bacterial biofilms. The dispersion inducing factor will be isolated from spent culture medium by solvent extraction and purified by chromatography followed by standard structural chemical analysis. This analysis will include infrared spectroscopy for functional group identification, mass spectrometry and nuclear magnetic resonance spectroscopy. The isolated factor will be tested to determine its effectiveness as a dispersion inducer throughout each stage of the isolation process. Isolated fractions containing the inducer compound(s) will be added to simulated biofilms using a rapid screening technique and these will be verified in tests with continuous culture biofilm populations. This work will incorporate undergraduate student research participation during the academic year and summer term. Student training in the departments of chemistry and biology will include laboratory sections on spectral identification of factors in spent medium and antibiotic efficacy testing of dispersion induced and non-induced bacterial biofilms.Microbial biofilms in infections and in industrial systems present significant problems due to their resistance to treatment by microbicidal agents. This resistance is due in large part to the aggregated nature of cells in biofilms. It has been discovered in Dr. Davies' laboratory that cell-free spent medium recovered from high cell density cultures of P. aeruginosa is capable of inducing biofilm autodispersion when added exogenously to growing biofilms. The proposed work is expected to provide a novel approach to control biofilm formation and persistence by P. aeruginosa and lead to the development of strategies for enhanced biofilm control and removal in industrial, household and medical applications.