Dealing with Antibiotic Resistance: Antisense Technology

应对抗生素耐药性：反义技术

• 批准号: 8574486
• 负责人: MARCELO E TOLMASKY
• 金额: $ 39.8万
• 依托单位: CALIFORNIA STATE UNIVERSITY FULLERTON
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8574486
• 关键词: Acetyltransferase; Address; Amikacin; Aminoglycoside resistance; Aminoglycosides; Antibiotic Resistance; Antibiotic Therapy; Antibiotics; Antimicrobial Effect; Antimicrobial Resistance; Antisense Technology; Appearance; Bacterial Antibiotic Resistance; Bacterial Infections; Biological Assay; Biological Models; Cell division; Cells; Communities; Computer Assisted; DNA; Deoxyribonucleotides; Development; Docking; Drug resistance; Effectiveness; Enzymes; Escherichia coli; Essential Genes; Gene Expression; Genes; Goals; Grant; Growth; Health; Human; Hybrids; In Vitro; Infection; Infection prevention; Laboratories; Lead; Libraries; Life; Mediating; Medical; Messenger RNA; Molecular; Oligoribonucleotides; Operative Surgical Procedures; Pharmaceutical Preparations; Plasmids; Predisposition; Procedures; Proteins; RNase P; Research; Residual state; Resistance; Scanning; Staging; Technology; Testing; Transplantation; aminoglycoside 6' -N-acetyltransferase; analog; base; cell growth; chemotherapy; clinically relevant; combat; combinatorial; design; fight against; in vivo; infectious disease treatment; inhibitor/antagonist; locked nucleic acid; monomer; nuclease; pathogen; research study; scaffold; small molecule; success; technology development; tool; uptake

DESCRIPTION (provided by applicant): Antimicrobial resistance is a growing problem that threatens treatment of infectious diseases and numerous medical procedures. It is well known that the introduction of new antibiotics is slow and costly. In consequence, this proposal concentrates on a critical aspect of the fight against the problem of bacterial resistance to antibiotics: the search for strategies aimed at preserving the effectiveness of currently available drugs. Our model system is the aminoglycoside 6'-N-acetyltransferase type Ib [AAC(6')-Ib], the most clinically relevant acetyltransferase among gram-negative pathogens, which mediates resistance to amikacin (Ak) and other aminoglycosides. These antibiotics are an important component of the armamentarium against serious infections caused by several gram-negative pathogens. The long term goal of this research is to develop pharmacological tools that in combination with Ak overcome the presence of aac(6')-Ib and can be successfully used to treat Ak-resistant infections. We have identified oligoribonucleotide sequences, known as external guide sequences (EGSs), that elicit RNase P-mediated cleavage of aac(6')-Ib and ftsZ mRNA and result in a reduction of the levels of resistance to Ak and inhibition of cell division, respectively. Furthermore, we determined that nuclease resistant oligoribonucleotide analogs composed of locked nucleic acids and deoxyribonucleotide monomers (LNA/DNA) behave as EGSs. One aim of this project is to generate efficient LNA/DNA EGSs that can penetrate the cells and inhibit expression of the resistance gene aac(6')-Ib. These compounds will be used in combination with Ak (LNA/DNA EGSaac/Ak) to achieve phenotypic conversion to susceptibility to Ak. However since a common problem of antisense strategies is that the inhibitory activity is not potent enough for an effective antimicrobial effect we will design compounds that act synergistically with the mix LNA/DNA EGSaac/Ak. We will identify inhibitors of AAC(6')-Ib that will eliminate the activity of any enzyme produced by residual expression of the resistance gene. We will also design LNA/DNA EGSs that will interfere with expression of the E. coli and A. baumannii essential cell division protein FtsZ by eliciting RNase P-cleavage of ftsZ mRNA genes. Combinations consisting of the mix LNA/DNA EGSaac/Ak plus an AAC(6')-Ib inhibitor and/or an LNA/DNA EGS targeting ftsZ will be tested to determine their ability to inhibit growth of E. coli and A. baumannii harboring aac(6')-Ib.

描述（由申请人提供）：抗菌素耐药性是一个日益严重的问题，威胁着传染病的治疗和许多医疗程序。众所周知，新抗生素的引入速度缓慢且成本高昂。因此，该提案集中于解决细菌对抗生素耐药性问题的一个关键方面：寻找旨在保持现有抗生素有效性的策略。 药物。我们的模型系统是氨基糖苷类 6'-N-乙酰转移酶 Ib 型 [AAC(6')-Ib]，它是革兰氏阴性病原体中临床最相关的乙酰转移酶，可介导对阿米卡星 (Ak) 和其他氨基糖苷类的耐药性。这些抗生素是对抗多种革兰氏阴性病原体引起的严重感染的药物的重要组成部分。这项研究的长期目标是开发与 Ak 结合的药理学工具，克服 aac(6')-Ib 的存在，并可成功用于治疗 Ak 耐药感染。我们已经鉴定出寡核糖核苷酸序列，称为外部引导序列 (EGS)，可引发 RNase P 介导的 aac(6')-Ib 和 ftsZ mRNA 裂解，并导致 Ak 抗性水平降低并抑制细胞分裂， 分别。此外，我们确定由锁定核酸和脱氧核糖核苷酸单体（LNA/DNA）组成的核酸酶抗性寡核糖核苷酸类似物表现得像EGS。该项目的一个目标是生成有效的 LNA/DNA EGS，它可以穿透细胞并抑制抗性基因 aac(6')-Ib 的表达。这些化合物将与 Ak (LNA/DNA EGSaac/Ak) 结合使用，以实现对 Ak 敏感性的表型转化。然而，由于反义策略的一个常见问题是抑制活性不足以发挥有效的抗菌作用，我们将设计与 LNA/DNA EGSaac/Ak 混合物协同作用的化合物。我们将鉴定AAC(6')-Ib的抑制剂，其将消除由抗性基因的残余表达产生的任何酶的活性。我们还将设计 LNA/DNA EGS，通过引发 ftsZ mRNA 基因的 RNase P 切割来干扰大肠杆菌和鲍曼不动杆菌必需细胞分裂蛋白 FtsZ 的表达。将测试由 LNA/DNA EGSaac/Ak 混合物加上 AAC(6')-Ib 抑制剂和/或靶向 ftsZ 的 LNA/DNA EGS 组成的组合，以确定其抑制大肠杆菌和鲍曼不动杆菌生长的能力aac(6')-Ib。