Novel molecular targets to combat antibiotic resistance: probing the assembly dynamics of a bacterial mitotic spindle

对抗抗生素耐药性的新分子靶点：探索细菌有丝分裂纺锤体的组装动力学

• 批准号: G0801162/1
• 负责人: Daniela Barillà
• 金额: $ 48.13万
• 依托单位: University of York
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=G0801162%2F1
• 关键词: Novel; molecular; targets; combat; antibiotic

Bacteria resistant to multiple antibiotics are a growing hazard to human health. When bacteria are not killed by a first antibiotic, the treatment has to be switched to a second or third alternative drug. Sometimes no alternative drug is available. Thus antibiotic resistance costs lives and money and puts a heavy burden on health care resources: it has been estimated that the costs for the NHS amount to around #1 billion a year. The emergence of superbugs among bacterial populations results from naturally occurring phenomena in the genetic patrimony of bacteria, which consists of a single circular (more rarely linear) chromosome of DNA and sometimes smaller circles of DNA, called plasmids. Resistance can develop in a bacterium as a consequence of a change or mutation in its chromosomal DNA or by acquisition of a plasmid carrying resistance genes from another bacterium. Plasmids are mobile genetic elements that are able to transfer from one bacterium to another of the same or different species. This mobility is dangerous as it foments the dissemination of antibiotic resistance genes. Multidrug resistance plasmids harbour their own survival kit, a partition cassette, consisting of two genes and a stretch of noncoding DNA. This cassette ensures accurate segregation of the plasmids from one generation to the next at cell division. When this system malfunctions, the plasmid is not stably inherited and is ultimately lost. In our laboratory, we have been investigating the molecular mechanisms involved in the inheritance and maintenance of the multidrug resistance plasmid TP228, which contains genes responsible for the resistance to six different antibiotics. The partition cassette of TP228 contains two genes, designated parF and parG, and a region of noncoding DNA. The protein specified by the parF gene is very peculiar as it forms cable-like filaments that can be seen by using an electron microscope. The protein specified by the parG gene is a DNA-binding factor contacting the noncoding DNA region on the plasmid. The aims of this project are: to explore the dynamics of the interaction of the ParF and ParG proteins in the cell; to investigate the mechanism whereby ParG helps the assembly of ParF into cable-like structures; and to identify other bacterial proteins that associate with the ParF-ParG complex. These studies will allow us to learn more about the mechanism whereby plasmids are maintained in bacterial cells and will identify novel targets for the development of new antimicrobial agents.

对多种抗生素产生抗药性的细菌对人类健康构成越来越大的威胁。当第一种抗生素没有杀死细菌时，治疗必须切换到第二或第三种替代药物。有时没有替代药物可用。因此，抗生素耐药性造成了生命和金钱的损失，并给卫生保健资源带来了沉重的负担：据估计，NHS每年的费用约为10亿美元。细菌种群中超级细菌的出现是细菌遗传中自然发生的现象的结果，细菌的遗传由单个环形(较少呈线性)的DNA染色体组成，有时还包括被称为质粒的较小的DNA环。由于细菌染色体DNA的改变或突变，或者通过从另一种细菌获得携带耐药基因的质粒，可以在细菌中产生耐药性。质粒是可移动的遗传元件，能够从一种细菌转移到同一或不同物种的另一种细菌。这种流动性是危险的，因为它会煽动抗生素耐药性基因的传播。多药耐药质粒有自己的生存工具箱，一个分区盒，由两个基因和一段非编码DNA组成。这个盒式磁带确保了在细胞分裂时从一代到下一代的质粒的准确分离。当这个系统发生故障时，质粒不会稳定遗传，最终会丢失。在我们的实验室里，我们一直在研究多药耐药质粒TP228的遗传和维持的分子机制，它包含了与六种不同抗生素耐药有关的基因。TP228的分区盒包含两个基因，命名为parf和parG，以及一个非编码区的DNA。由parf基因指定的蛋白质非常特殊，因为它形成了电缆状的细丝，可以用电子显微镜看到。由parG基因指定的蛋白质是一种DNA结合因子，与质粒上的非编码DNA区域接触。本项目的目的是：探索PARF和PARG蛋白在细胞中相互作用的动力学；研究PARG帮助PARF组装成缆状结构的机制；以及鉴定与PARF-PARG复合体相关的其他细菌蛋白。这些研究将使我们能够更多地了解细菌细胞中保持质粒的机制，并将为开发新的抗菌剂确定新的靶点。