Mapping the binding site of class D beta-lactamase enzymes for inhibitor design a

绘制 D 类 β-内酰胺酶的结合位点以进行抑制剂设计

• 批准号: 8103718
• 负责人: Rachel Powers
• 金额: $ 31.98万
• 依托单位: GRAND VALLEY STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-15 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8103718
• 关键词: Accounting; Acids; Active Sites; Affinity; American; Antibiotic Resistance; Antibiotics; Binding; Binding Sites; Biochemistry; Biological Assay; Biological Sciences; Boronic Acids; Carbapenems; Cell Wall; Cephalosporins; Chemicals; Chemistry; Clavulanic Acids; Clinical; Complex; Consensus; Crystallization; Data Collection; Docking; Drug Design; Enzyme Inhibitor Drugs; Enzyme Inhibitors; Enzymes; Epitopes; Exhibits; Fostering; Future; Goals; Grant; Lactamase; Lactams; Ligands; Maps; Mentors; Mission; Modification; Molecular; Molecular Biology; Monobactams; Multienzyme Complexes; Penicillins; Peptidyltransferase; Public Health; Reporting; Research; Resistance; Roentgen Rays; Side; Site; Societies; Staging; Structure; Structure-Activity Relationship; Students; Testing; United States National Institutes of Health; Variant; X-Ray Crystallography; analog; bacterial resistance; base; beta-Lactamase; beta-lactamase PSE-2; career; crosslink; design; enzyme activity; enzyme substrate; functional group; inhibitor/antagonist; novel; protein purification; research and development; research study; resistance mechanism; response; skills; symposium

DESCRIPTION (provided by applicant): ?-lactams, like penicillin and the cephalosporins, are the most widely prescribed class of antibiotics in clinical use today. In response to their extensive use and misuse, resistance has developed and is now one of the most pressing public health crises of the 21st century. Many resistant bacteria express ?-lactamase enzymes. These enzymes hydrolyze the defining lactam ring, rendering them inactive toward their original target, the transpeptidases that crosslink the bacterial cell wall. ?-lactamases are categorized into four, distinct classes (A, B, C, and D) based on sequence similarity and mechanism of action. In an effort to overcome resistance, inhibitors have been developed to block the activity of these enzymes. Of particular concern are the class D ?-lactamases, or oxacillinases, which are not typically inhibited by the classic ?-lactam- based inhibitors, like clavulanic acid, and are able to hydrolyze several of the most potent ?-lactams in clinical use, the oxyimino cephalosporins and the carbapenems. In part, resistance derives from the structural similarity of the inhibitors to the ?-lactams themselves, both containing a ?-lactam ring. Therefore an urgent need exists for novel inhibitors that do not resemble the ?-lactam substrates. However most structure-based design efforts rely on modification of existing ?-lactam antibiotics. Few attempts have been made to formally map out the binding determinants of a target active site to aid in the discovery of a novel, non-?-lactam inhibitor. This proposal offers a combined approach to formally map the active sites of the class D ?-lactamases, OXA-1 and OXA- 24/40, two highly relevant antibiotic resistance targets. The specific aims of this proposal employ a structure-based consensus overlay approach to identify and characterize the binding sites of OXA-1 and OXA-40. Information from this consensus map of binding sites will be used to discover novel, non-?-lactam inhibitors for these key resistance enzymes using molecular docking. PUBLIC HEALTH RELEVANCE: Currently, antibiotic resistance is one of the most pressing public health crises of the 21st century, and ?-lactamases are the most widespread resistance mechanism to ?-lactam antibiotics. The proposed research is relevant to the mission of the NIH because a better understanding of the structure-function relationship of the class D ?-lactamases OXA-1 and OXA-24/40 will aid in the design and discovery of novel inhibitors for these key targets in bacterial resistance to ?-lactam antibiotics.

描述（由申请人提供）：内酰胺类如青霉素和头孢菌素类是当今临床使用最广泛的抗生素处方类别。由于这些药物的广泛使用和滥用，耐药性不断发展，现已成为世纪最紧迫的公共卫生危机之一。许多耐药细菌表达？-内酰胺酶这些酶水解限定的内酰胺环，使它们对它们的原始靶标（交联细菌细胞壁的转肽酶）无活性。?-基于序列相似性和作用机制，内酰胺酶被分为四个不同的类别（A、B、C和D）。为了克服耐药性，已经开发了抑制剂来阻断这些酶的活性。特别值得关注的是D类？内酰胺酶或苯唑西林酶，这些酶通常不被经典的？内酰胺类抑制剂，如克拉维酸，能够水解几种最有效的？临床使用的内酰胺类、氧亚氨基头孢菌素类和碳青霉烯类。在某种程度上，耐药性来自于抑制剂与？内酰胺本身，两者都含有？-内酰胺环。因此，迫切需要新的抑制剂，不类似于？内酰胺底物。然而，大多数基于结构的设计工作都依赖于对现有结构的修改。内酰胺类抗生素很少有人试图正式绘制出目标活性位点的结合决定簇，以帮助发现一种新的、非？内酰胺抑制剂。这个建议提供了一个综合的方法，正式映射的活动网站的类D？- OXA-1和OXA- 24/40是两种高度相关的抗生素耐药性靶标。该提案的具体目的是采用基于结构的共识覆盖方法来鉴定和表征OXA-1和OXA-40的结合位点。从这个结合位点的共识图的信息将被用来发现新的，非？这些关键耐药酶的内酰胺抑制剂使用分子对接。 公共卫生相关性：目前，抗生素耐药性是21世纪最紧迫的公共卫生危机之一，内酰胺酶是最广泛的耐药机制？-内酰胺类抗生素拟议的研究与NIH的使命有关，因为更好地了解D？内酰胺酶OXA-1和OXA-24/40将有助于设计和发现针对细菌耐药中这些关键靶点的新型抑制剂。内酰胺类抗生素