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Mechanism of Quinolone Resistance

喹诺酮类耐药机制

基本信息

批准号：
10588482
负责人：
NEIL OSHEROFF
金额：
--
依托单位：
VETERANS HEALTH ADMINISTRATION
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-10-01 至 2023-03-22
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10588482
关键词：
Acinetobacter baumannii Active Sites Affect Amino Acids Anti-Bacterial Agents Aspartic Acid Bacillus anthracis Bacterial Drug Resistance Bacterial Infections Binding Biological Models Bypass Cell Death Cell Death Induction Centers for Disease Control and Prevention (U.S.)Ciprofloxacin Clinical Complex DNA DNA Damage DNA Double Strand Break DNA Maintenance DNA Topoisomerase IV Data Drug Interactions Drug resistance Drug usage Enzyme Inhibition Enzyme Interaction Enzymes Escherichia coli Fluoroquinolones Francisella tularensis Genetic Materials Genome Goals Gonorrhea Grant Handedness Health Hospital Administration In Vitro Incidence Infection Ions Laboratories Libraries Ligation Mediating Metals Military Personnel Monitor Mutation Mycobacterium tuberculosis Neisseria gonorrhoeae Neurofibrillary Tangles Oral Pharmaceutical Preparations Phase III Clinical Trials Physiological Positioning Attribute Publishing Research Resistance Role Serine Sexually Transmitted Diseases Single-Stranded DNA Staphylococcus aureus Structure Structure-Activity Relationship Superhelical DNA Topoisomerase Topoisomerase II Topoisomerase Inhibitors Toxin United States Department of Veterans Affairs Veterans Water World Health Organization antimicrobial bacterial resistance cell type cellular targeting clinical efficacy design drug action drug structure experimental study fluoroquinolone resistance in vitro activity member military veteran mutant novel novel therapeutics pathogen quinolone resistance resistance mechanism resistance mutation targeted agent

项目摘要

Fluoroquinolones, such as ciprofloxacin, are among the most efficacious and broad-spectrum oral antibacterials in clinical use. The World Health Organization lists them in their five “Highest Priority Critically Important Anti- microbials,” and these drugs are the most heavily prescribed antibacterials at Veterans Administration hospitals. The cellular targets of fluoroquinolones are the bacterial type II topoisomerases, gyrase and topoisomerase IV. These essential enzymes regulate DNA under- and overwinding and remove knots and tangles from the genome by generating transient double-stranded breaks in the genetic material. Fluoroquinolones act by increasing levels of double-stranded DNA breaks generated by gyrase and topoisomerase IV, which converts these enzymes into cellular toxins that fragment the genome. Both gyrase and topoisomerase IV are physiological targets for fluoro- quinolones, but their relative importance to drug action appears to be species- and drug-dependent. There is a growing crisis in antibacterial resistance and fluoroquinolone resistance is becoming prevalent. This resistance is threatening the clinical efficacy of fluoroquinolones and their use to treat US Veterans. For example, fluoroquinolones were used routinely to treat gonorrhea (which is caused by Neisseria gonorrhoeae), a sexually transmitted disease that is prevalent in the military and elevated in Veteran populations, starting in 1993. However, their use as front-line therapy was discontinued in 2006 due to the high incidence of resistance. Initial fluoroquinolone resistance is most often associated with specific mutations in gyrase and/or topoisomerase IV that occur at a serine residue (originally described as Ser83 in the GyrA subunit of Escherichia coli gyrase) and a glutamic/aspartic acid residue 4 amino acids downstream. Based on a published structure and functional studies from the Osheroff laboratory, these residues are proposed to anchor a water-metal ion bridge that serves as the primary conduit between fluoroquinolones and gyrase/topoisomerase IV. By characterizing fluoroquinolone-enzyme interactions, the PI has designed novel drugs that overcome resistance mutations in Mycobacterium tuberculosis gyrase and Bacillus anthracis gyrase and topoisomerase IV. The identification and characterization of novel agents that act against these well-validated topoisomerase targets and overcome fluoroquinolone resistance could have important ramifications for the health of Veterans. Recently, two new classes of gyrase/topoisomerase IV-targeted agents have been described that appear to overcome this resistance, Novel Bacterial Topoisomerase Inhibitors (NBTIs) and Spiropyrimidinetriones (SPTs). Members of these classes, gepotidacin (NBTI) and zoliflodacin (SPT), have advanced to phase 3 clinical trials. NBTIs are unique, as they induce single- rather than double-stranded enzyme-generated DNA breaks. However, little is known about the actions of NBTIs and SPTs against gyrase/topoisomerase IV or their basis of resistance. There is an urgent need to develop more effective drugs that display activity against fluoroquinolone-resistant bacteria. The premise underlying the proposed research is that understanding how drugs interact with their enzyme targets places us in a far better position to develop agents that overcome resistance. Thus, the specific aims of this proposal are to 1) determine the mechanistic basis for fluoroquinolone action and resistance with gyrase and topoisomerase IV across species; and 2) determine the mechanistic basis for the actions of NBTIs and SPTs against gyrase and topoisomerase IV across species. Proposed experiments will build upon previous studies from the Osheroff laboratory and preliminary data on the mechanism of bacterial type II topoisomerases and their interactions with fluoroquinolones, NBTI, and SPTs. Research will benefit greatly from the broad library of wild-type and drug-resistant gyrase/topoisomerase IV that the Osheroff laboratory has established. This library includes enzymes from B. anthracis, E. coli, Staphylococcus aureus, M. tuberculosis, Neisseria gonorrhoeae, Francisella tularensis, and Acinetobacter baumannii. Many of these pathogens routinely affect the health of US Veterans. Initial studies will focus on N. gonorrhoeae, M. tuberculosis, and E. coli as the model systems.

氟喹诺酮类药物，如环丙沙星，是最有效的广谱口服抗菌药之一

项目成果

期刊论文数量（14）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

1,3-Dioxane-Linked Novel Bacterial Topoisomerase Inhibitors: Expanding Structural Diversity and the Antibacterial Spectrum.

1,3-二恶烷连接的新型细菌拓扑异构酶抑制剂：扩大结构多样性和抗菌谱。

DOI：
10.1021/acsmedchemlett.2c00111
发表时间：
2022
期刊：
ACS medicinal chemistry letters
影响因子：
4.2
作者：
Lu,Yanran;Mann,ChelseaA;Nolan,Sheri;Collins,JessicaA;Parker,Elizabeth;Papa,Jonathan;Vibhute,Sandip;Jahanbakhsh,Seyedehameneh;Thwaites,Mary;Hufnagel,David;Hazbón,ManzourH;Moreno,Jane;Stedman,TimothyT;Wittum,Thomas;Wozniak,D
通讯作者：
Wozniak,D

Telling Your Right Hand from Your Left: The Effects of DNA Supercoil Handedness on the Actions of Type II Topoisomerases.

DOI：
10.3390/ijms241311199
发表时间：
2023-07-07
期刊：
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
影响因子：
5.6
作者：
Jian, Jeffrey Y. Y.;Osheroff, Neil
通讯作者：
Osheroff, Neil

Basis for the discrimination of supercoil handedness during DNA cleavage by human and bacterial type II topoisomerases.

人类和细菌 II 型拓扑异构酶 DNA 切割过程中超螺旋旋向判别的基础。

DOI：
10.1093/nar/gkad190
发表时间：
2023
期刊：
Nucleic acids research
影响因子：
14.9
作者：
Jian,JeffreyY;McCarty,KevinD;Byl,JoAnnW;Guengerich,FPeter;Neuman,KeirC;Osheroff,Neil
通讯作者：
Osheroff,Neil

Getting stressed over topoisomerase I poisons.