The Pseudomonas Aeruginosa Biofilm Dispersion Response

描述(申请人提供)：我们实验室最近的研究表明，铜绿假单胞菌对废旧培养基中的可溶性有机因素做出反应，这些因素会导致生物膜细胞团的解体，并导致从生物膜到浮游生活方式的转变。初步结果表明，与未被诱导分散的生物膜细菌相比，这些分散的细菌对抗生素治疗的敏感性要高得多。我们从废弃的铜绿假单胞菌固定相培养物(以葡萄糖为唯一碳源)中提取和纯化了有机部分，并对铜绿假单胞菌、肺炎克雷伯菌、大肠杆菌、奇异变形杆菌、化脓性链球菌、金黄色葡萄球菌和白色念珠菌形成的生物膜进行了测试。我们还对这种提取物与这些微生物的混合物种生物膜进行了测试，与对照生物膜相比，在所有情况下都检测到了统计上显著的分散性(P&lt；0.05在所有被检测的样本中)。通过核磁共振、红外光谱和质谱学对提取的有机物质的活性高效液相色谱组分进行分析，鉴定出一种小的信使分子，当以纯形式合成并添加到铜绿假单胞菌的生物膜中时，复制了使用纯化的废培养基萃取物可检测到的分散反应。我们希望同时测试提取的有机分散诱导剂以及合成的分子来研究铜绿假单胞菌的分散响应机制。目前，关于蛋白质合成的作用或弥散反应中裂解酶的释放，我们的信息有限。当生物膜细菌在弥散反应过程中转变为浮游细胞时，我们对表型和转录调控方面的变化的理解也受到限制。因此，这项建议旨在研究提取的有机分散诱导剂在生物被膜细菌向浮游生活方式转变时诱导生理变化的作用。 公共卫生相关性：目前的申请提出的工作将产生重要的信息，有助于了解铜绿假单胞菌的生物被膜分散反应。这项拟议的研究结果有望带来治疗细菌生物膜的新的和改进的策略。一种可以在生物膜中引起分散的化合物的潜在商业可能性包括加强对生物膜感染的治疗、改进对烧伤的治疗、改善表面生物膜的去除、改善医院的卫生、更有效的清洁产品以改善家庭健康等。

DESCRIPTION (provided by applicant): Recent studies in our laboratory have demonstrated that P. aeruginosa respond to soluble organic factors in spent culture medium that induce the disaggregation of biofilm cell clusters and result in a switch from a biofilm to a planktonic lifestyle. Preliminary results have demonstrated that these dispersed bacteria are significantly more susceptible to antibiotic treatment when compared to biofilm bacteria that have not been induced to disperse. We have extracted and purified the organic fraction from spent stationary phase cultures of P. aeruginosa (using glucose as a sole carbon source), and have tested this extract against biofilms formed by P. aerugjnosa, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Streptococcus pyogenes, Staphylococcus aureus, and Candida albicans. We have also tested this extract against mixed species biofilms with these organisms and have detected statistically significant dispersion in all cases when compared to control biofilms (p < 0.05 in all samples assayed). Analysis of active HPLC fractions of the extracted organic material by NMR, IR and mass spectroscopy, has lead to the identification of a small messenger molecule which when synthesized in pure form and added to biofilms of P. aeruginosa, replicates the dispersion response detectable using the purified spent culture medium extract. We wish to test both the extracted organic dispersion inducer as well as the synthesized molecule to investigate the mechanism of the dispersion response in P. aeruginosa. Currently we have limited information regarding the role of protein synthesis or the release of lytic enzymes during the dispersion response. We are also limited in our understanding of the changes that occur with respect to phenotype and transcriptional regulation when biofilm bacteria transition to planktonic cells during the dispersion response. This proposal therefore, aims to investigate the role of the extracted organic dispersion inducer in inducing a change in the physiology of biofilm bacteria as they transition to a planktonic lifestyle. PUBLIC HEALTH RELEVANCE: The current application proposes work that will yield important information leading to an understanding of the biofilm dispersion response in P. aeruginosa. Findings from the proposed research are expected to lead to novel and improved strategies for the treatment of bacterial biofilms. The potential commercial possibilities for a compound that can induce dispersion in biofilms include enhanced treatment of biofilm infections, improved treatment of burns, improved removal of biofilm from surfaces, improved hygiene in hospitals, more effective cleaning products to improve health in the home, and others.