AHL Hydrolase Mediated Biofilm Inhibition

AHL 水解酶介导的生物膜抑制

• 批准号: 7538891
• 负责人: Robert J. Turner
• 金额: $ 13.3万
• 依托单位: LYBRADYN, INC.
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7538891
• 关键词: Admission activity; American Type Culture Collection; Antibiotic Resistance; Antibiotics; Apoenzymes; Bacteria; Bacterial Infections; Binding; Chemical Warfare Agents; Class; Coculture Techniques; Complex; Development; Devices; Drug Formulations; Effectiveness; Elements; Engineering; Enzymatic Biochemistry; Enzymes; Genetic Engineering; Gluconolactonase; Gram-Negative Bacteria; Growth; Homologous Gene; Hospitals; Host Defense Mechanism; Hydrolase; Hydrolysis; Implant; Infection; Kinetics; Laboratory Research; Lactones; Lead; Letters; Life; Link; Liquid substance; Literature; Marines; Marketing; Mediating; Medical Device; Microbial Biofilms; Molecular; N-(3-oxododecanoyl)homoserine lactone; N-butyrylhomoserine lactone; Nosocomial Infections; Numbers; Organism; Patients; Pesticides; Phase; Phosphoric Triester Hydrolases; Prevention; Process; Production; Pseudomonas; Pseudomonas aeruginosa; Public Health; Range; Rate; Relative (related person); Rhodococcus; Series; Signal Transduction; Small Business Funding Mechanisms; Small Business Innovation Research Grant; Solubility; Structure; Surface; System; Testing; Time; Virulence Factors; Work; amidase; base; clinically relevant; commercialization; concept; directed evolution; enzyme structure; homoserine lactone; implantation; nosocomial infection control; novel; pathogen; physical property; prevent; quorum sensing; research and development; thermostability

DESCRIPTION (provided by applicant): Bacterial biofilms thwart the control of nosocomial infections, such as those resulting from medical device implantation. Elevated levels of one or more quorum sensing (QS) signals have been linked to the formation of bacterial biofilms, which makes eradication of bacteria colonizing the growth-amenable surfaces of implants difficult due to their biofilm-mediated resistance to antibiotics and host defense mechanisms. Therefore, it is desirable to develop ways to control quorum sensing and thus biofilm formation of P. aeruginosa and other Gram-negative pathogens. As with many Gram-negative organisms, N-acyl homoserine lactones (AHL) function as major QS signals for P. aeruginosa, specifically N-butanoyl-l-homoserine lactone (C(4)-HSL) and N-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-C(12)-HSL). A small number of enzymes have been found that show potential for modulating QS by degrading AHLs, but there development has been limited. We have isolated enzymes from Geobacilli that possess demonstrable activity toward AHLs (functioning as lactonases) and are able to disrupt AHL-dependent processes of test organisms in liquid culture, including P. aeruginosa biofilm formation. Our most active Geobacillus enzyme, a very stable, soluble enzyme that can be readily purified, is already being expressed in a commercially viable system. We propose to further characterize these enzymes, relative to known AHL lactonases, to judge their suitability for our ultimate objective to formulate these enzymes into coatings for medical device products. PUBLIC HEALTH RELEVANCE Preventing medical device-related Pseudomonas aeruginosa (PA) infections by inhibiting quorum sensing (QS) dependent processes such as biofilm formation, allowing host defense mechanisms and antibiotic strategies to be more effective, is a concept that holds great potential. Towards these ends, we discovered enzymes isolated from species of Geobacillus are capable of hydrolyzing the lactone ring of N-acyl-L- homoserine lactones, the molecular trigger of bacterial QS for Gram-negative bacteria. Furthermore, co-culturing purified these Geobacillus enzymes inhibits QS-dependent processes, such as PA biofilm formation. In Phase I, we will thoroughly characterize the lactonase activities of our Geobacillus enzymes. We will also quantitatively compare our Geobacillus enzymes to other emerging lactonase enzymes.

描述（由申请人提供）：细菌生物膜阻碍医院感染的控制，例如由医疗器械植入引起的感染。一种或多种群体感应（QS）信号的水平升高与细菌生物膜的形成有关，由于细菌生物膜介导的对抗生素的抗性和宿主防御机制，细菌生物膜的形成使得难以根除定植在植入物的可生长表面上的细菌。因此，期望开发控制群体感应并因此控制铜绿假单胞菌和其他革兰氏阴性病原体的生物膜形成的方法。与许多革兰氏阴性生物一样，N-酰基高丝氨酸内酯（阿勒）作为铜绿假单胞菌的主要QS信号，特别是N-丁酰基-1-高丝氨酸内酯（C（4）-HSL）和N-（3-氧代十二烷酰基）-1-高丝氨酸内酯（3-氧代-C（12）-HSL）。已经发现少量的酶显示出通过降解AHLs来调节QS的潜力，但是其开发受到限制。我们已经从土芽孢杆菌中分离出了对AHL具有明显活性的酶（作为内酯酶起作用），并且能够破坏液体培养物中测试生物体的AHL依赖性过程，包括铜绿假单胞菌生物膜形成。我们最活跃的土芽孢杆菌酶是一种非常稳定的可溶性酶，可以很容易地纯化，已经在商业上可行的系统中表达。我们建议进一步表征这些酶，相对于已知的阿勒内酯酶，以判断它们是否适合我们的最终目标，将这些酶配制成医疗器械产品的涂层。公共卫生相关性通过抑制生物膜形成等群体感应（QS）依赖性过程，使宿主防御机制和抗生素策略更有效，预防医疗器械相关铜绿假单胞菌（PA）感染，是一个具有巨大潜力的概念。为此，我们发现从土芽孢杆菌属物种中分离的酶能够水解N-酰基-L-高丝氨酸内酯的内酯环，其是革兰氏阴性菌的细菌QS的分子触发剂。此外，共培养纯化的这些土芽孢杆菌酶抑制QS依赖性过程，如PA生物膜形成。在第一阶段，我们将彻底表征我们的土芽孢杆菌酶的内酯酶活性。我们还将定量比较我们的土芽孢杆菌酶与其他新兴的内酯酶。