Enzyme-containing Anti-biofilm Coatings for Urological Catheters

描述（由申请人提供）：预防植入医疗器械和材料（包括泌尿导管）后的感染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，其在污染时通过细菌细胞的表面定殖在装置或材料表面上形成。尽管在开发抗生物膜材料和涂层方面做出了相当大的努力，但在抑制导管中的生物膜相关感染方面几乎没有取得进展，这给全球医疗保健系统带来了巨大的负担。该提案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抵抗导管表面上的生物膜形成。这种策略将通过共价固定的群体淬灭酶氨酰化酶，催化N-酰基氨基酸的降解，在聚氨酯涂料进行研究。我们假设，氨基酰化酶在聚氨酯涂层的固定化将促进生物催化水解的群体信号，诱导组装的微生物菌群的表面上。氨基酰化酶将通过将酶分散在多异氰酸酯和多元醇预聚物的水性混合物中而被具体地固定在聚氨酯涂层内。酶在水性聚合反应中的分散促进酶经由酶表面上的官能团与聚合物网络的共价偶联。固定化后，将研究氨基酰化酶的活性和稳定性，以了解固定化如何影响酶的功能。此外，我们将确定所得涂层对铜绿假单胞菌形成生物膜的抑制活性，铜绿假单胞菌在导管中的生物膜感染中普遍存在。因此，本研究的具体目标是：1）通过多点共价固定表征氨基酰化酶在双组分水性聚氨酯涂层中的掺入，2）确定含氨基酰化酶涂层抑制铜绿假单胞菌群体感应的程度，以及3）证明模型表面上含氨基酰化酶涂层对铜绿假单胞菌生物膜形成的预防。我们期望在完成这项研究，以充分了解固定化氨基酰化酶活性和群体淬灭以及生物膜抑制涂层之间的关系。最终，这项工作将有相当大的影响，在减少患者的痛苦和医疗保健成本与泌尿系统导管相关的感染以及感染的血管导管。更广泛地说，此类涂层还可用于预防隐形眼镜（生物膜也很普遍）以及其他植入式生物材料和医疗器械的感染。

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.