Ribosome Quality Control Mechanisms in Gram-Positive Bacteria

革兰氏阳性细菌的核糖体质量控制机制

基本信息

批准号：
10796401
负责人：
Heather Feaga
金额：
$ 3.98万
依托单位：
CORNELL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-08-01 至 2027-05-31
项目状态：
未结题

项目摘要

Project Summary: Although bacterial ribosomes have been biochemically interrogated for decades, unknown mechanisms of regulation and quality control are regularly uncovered and targeted with new antibiotics. Major differences in translation between Gram-negative and Gram-positive organisms have come to light in recent years. Although approximately half of antibiotic-resistant infections are caused by Gram-positive bacteria, major gaps remain in our understanding of how Gram-positives perform ribosome quality control. To address these gaps, my laboratory will focus on two major research areas. 1) We will identify and characterize strategies used by Gram- positive bacteria to detect and rescue stalled ribosomes. Preliminary data from my lab supports a model in which ribosome stalling in B. subtilis and B. anthracis results in frameshifting and premature translation termination. This process is expected to result in toxic truncated proteins and trigger stress responses. We will test this model using biochemical, genetic, and structural approaches. 2) We will determine how ribosome flexibility can be used by the bacterial cell to expand coding capacity. Here, we will investigate how frameshifting and read-through of poorly terminating UAG stop-codons regulates gene expression and identify environmental inputs for this type of regulation. We will use biochemical, structural, and computational approaches to investigate the research themes described above. To further expand this research program, we will use unbiased high throughput genetics to uncover new mechanisms that prevent stalling and that regulate frameshifting and stop codon read- through.

项目概要：尽管细菌核糖体已经被生化研究了数十年，但未知的机制监管和质量控制定期被发现并以新抗生素为目标。主要差异在于近年来，革兰氏阴性和革兰氏阳性生物之间的翻译已被发现。虽然大约一半的抗生素耐药性感染是由革兰氏阳性菌引起的，但在我们对革兰氏阳性菌如何进行核糖体质量控制的理解。为了解决这些差距，我的实验室将重点关注两大研究领域。 1）我们将识别并描述 Gram- 使用的策略阳性细菌检测并拯救停滞的核糖体。我的实验室的初步数据支持一个模型，其中枯草芽孢杆菌和炭疽芽孢杆菌中的核糖体停滞会导致移码和过早翻译终止。这一过程预计会产生有毒的截短蛋白质并引发应激反应。我们将测试这个模型使用生物化学、遗传和结构方法。 2）我们将确定如何利用核糖体灵活性由细菌细胞扩大编码能力。在这里，我们将研究如何进行移码和通读不良终止 UAG 终止密码子调节基因表达并识别此类类型的环境输入的监管。我们将使用生物化学、结构和计算方法来调查研究上述主题。为了进一步扩展该研究计划，我们将使用无偏高通量遗传学揭示了防止停滞、调节移码和阻止密码子读取的新机制通过。