Enzyme-containing Anti-biofilm Coatings for Urological Catheters

描述(由申请人提供)：预防植入医疗设备和材料，包括尿路导管，是一项重大的临床挑战。这种感染的主要来源是细菌生物膜，它们通过污染后细菌细胞的表面定植形成在设备或材料表面。尽管在开发抗生物被膜材料和涂层方面做出了相当大的努力，但在抑制导管中与生物被膜相关的感染方面进展甚微，给世界各地的医疗系统带来了巨大的负担。这项建议的总体目标是开发一种新的策略，通过抑制表面相关细菌的群体感应来阻止导管表面生物膜的形成。这一策略将通过共价固定在聚氨酯涂料中催化N-酰基氨基酸降解的法定人数猝灭酶氨基酰基酶来进行研究。我们假设，氨基酰基酶在聚氨酯涂层中的固定化将促进诱导微生物联合体在表面组装的法定信号的生物催化水解。氨基酰基酶将通过将酶分散在多异氰酸酯和多元醇预聚体的水溶液混合物中，专门固定在聚氨酯涂料中。酶在水相聚合反应中的分散促进了酶通过酶表面的官能团与聚合物网络的共价偶联。在固定化后，将研究氨基酰基酶的活性和稳定性，以了解固定化对酶功能的影响。此外，我们还将确定所制得的涂层对铜绿假单胞菌生物膜形成的抑制活性，铜绿假单胞菌在导管生物膜感染中很常见。因此，这项研究的具体目标是：1)表征通过多点共价固定化在双组分水性聚氨酯涂料中掺入氨基酰基酶的情况；2)确定含氨基酰基酶涂料对铜绿假单胞菌群体感应的抑制程度；以及3)展示模型表面含氨基酰基酶涂料对铜绿假单胞菌生物膜形成的预防作用。我们预计在这项研究完成后，将充分了解固定化氨基酰基酶活性与群体猝灭以及涂层对生物膜抑制的关系。最终，这项工作将对减少与尿路导管相关感染以及血管导管感染相关的患者痛苦和医疗成本产生重大影响。更广泛地说，这种涂层还可以用于预防隐形眼镜以及其他植入性生物材料和医疗器械上的感染，在隐形眼镜上生物膜也很普遍。

DESCRIPTION (provided by applicant): The prevention of infections upon implantation of medical devices and materials, including, namely, urological catheters, represents a significant clinical challenge. A primary source of such infections is bacterial biofilms, which form on the device or material surface via the surface colonization of bacterial cells upon contamination. Despite considerable efforts to develop anti-biofilm materials and coatings, little progress has been made in inhibiting biofilm-related infections in catheters, placing an enormous burden on healthcare systems worldwide. The overall aim of this proposal is to develop a novel strategy to resist biofilm formation on catheter surfaces via inhibiting quorum sensing in surface-associated bacteria. This strategy will be investigated by covalently immobilizing the quorum quenching enzyme aminoacylase, which catalyzes the degradation of N-acyl amino acids, in polyurethane coatings. We hypothesize that the immobilization of aminoacylase in polyurethane coatings will facilitate the biocatalytic hydrolysis of quorum signals that induce the assembly of microbial consortia on surfaces. Aminoacylase will specifically be immobilized within polyurethane coatings via dispersion of the enzyme in an aqueous mixture of polyisocyanate and polyol prepolymers. Dispersion of the enzyme in the aqueous polymerization reaction facilitates covalent coupling of the enzyme to the polymer network via functional groups on the enzyme surface. Upon immobilization, the activity and stability of aminoacylase will be studied to understand how immobilization impacts enzyme function. Moreover, we will ascertain the inhibitory activity of the resulting coatings towards the formation of biofilms by Pseudomonas aeruginosa, which is prevalent in biofilm infections in catheters. Accordingly, the specific objectives of this research are to: 1) characterize the incorporation of aminoacylase in two-component waterborne polyurethane coatings via multipoint covalent immobilization, 2) determine the extent to which quorum sensing in P. aeruginosa by aminoacylase-containing coatings is inhibited, and 3) demonstrate the prevention of biofilm formation by P. aeruginosa by aminoacylase-containing coatings on model surfaces. We anticipate at the completion of this research to fully understand the relationship between immobilized aminoacylase activity and quorum quenching as well as biofilm inhibition by the coatings. Ultimately, this work will have considerable implications in reducing patient suffering and healthcare costs associated with urological catheter-related infections as well as infections from vascular catheters. More broadly, such coatings may also have utility in the prevention of infections on contact lenses, where biofilms are also prevalent, and on other implantable biomaterials and medical devices.