In vitro assembly of bacterial peptidoglycan in tethered lipid bilayer membranes

束缚脂质双层膜中细菌肽聚糖的体外组装

• 批准号: BB/D011574/1
• 负责人: Timothy Bugg
• 金额: $ 17.8万
• 依托单位: University of Warwick
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FD011574%2F1
• 关键词: vitro; assembly; bacterial; peptidoglycan; tethered

The spread of antibiotic-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae (the cause of pneumonia) poses a real threat to patient care in the UK health service, and has become a political issue in the 2005 general election. For the last 40 years we have taken penicillin for granted as a life-saving medicine, but there is now an urgent need to find new targets for antibacterial action. The mode of action of penicillin is to inhibit the final step of the assembly of peptidoglycan, a polysaccharide layer found on the surface of all bacteria. This transpeptidation step, which cross-links the peptidoglycan layer and gives it structural rigidity, is catalysed by the penicillin-binding proteins (PBPs). In spite of the large amount of work carried out on the penicillin and cephalosporin families of antibiotics, there are still very limited methods to study the reaction catalysed by the PBPs, because the substrates for these enzymes are complex lipid-linked intermediates found in the cell membrane. We have developed new techniques to study these lipid-linked steps. Using gold-coated chips, we can deposit tethered lipid bilayer membranes (TLBMs) on the surface of the chip, and we can use these devices to deposit the lipid II substrate for the PBP reaction. We can prepare these lipid II substrates in the lab, and can attach fluorescent labels, which allow us to monitor the reaction. In this project we want to use a range of surface science methods to study the reactions catalysed by the PBPs on TLBMs, which will allow us to a) develop new ways to find new antibacterial agents; b) study the reactions catalysed by PBPs from penicillin-resistant bacteria, and find out why they have become resistant to penicillin.

抗抗生素耐药细菌（例如耐甲氧西林金黄色葡萄球菌（MRSA）和耐青霉素的肺炎链球菌（肺炎的原因））对英国卫生服务中的患者护理构成了真正的威胁，并且已成为2005年的政治问题。在过去的40年中，我们将青霉素视为一种挽救生命的药物，但是现在迫切需要寻找新的抗菌作用目标。青霉素的作用方式是抑制肽聚糖组装的最后一步，肽聚糖是所有细菌表面上发现的多糖层。这种转换步骤通过青霉素结合蛋白（PBP）催化了肽聚糖层并赋予其结构刚度的链接。尽管对抗生素的青霉素和头孢菌素家族进行了大量工作，但仍有非常有限的方法研究PBPS催化的反应，因为这些酶的底物是在细胞膜中发现的复杂脂质连接的中间体。我们已经开发了新技术来研究这些脂质连接的步骤。使用镀金碎片，我们可以在芯片表面沉积束缚的脂质双层膜（TLBMS），我们可以使用这些设备将脂质II底物沉积用于PBP反应。我们可以在实验室中准备这些脂质II底物，并可以连接荧光标签，从而使我们能够监视反应。在这个项目中，我们希望使用一系列的表面科学方法来研究PBP在TLBMS上催化的反应，这将使我们能够a）开发新方法来寻找新的抗菌剂； b）研究来自耐青霉素的细菌PBP催化的反应，并找出为什么它们对青霉素具有抗药性。

项目成果

In vitro biosynthesis of bacterial peptidoglycan using D-Cys-containing precursors: fluorescent detection of transglycosylation and transpeptidation.

使用含 D-Cys 的前体进行细菌肽聚糖的体外生物合成：转糖基化和转肽作用的荧光检测。

• DOI: 10.1039/b819869a
• 发表时间: 2009
• 期刊: Chemical communications (Cambridge, England)
• 作者: Vinatier V

Antibiotic action and peptidoglycan formation on tethered lipid bilayer membranes.

• DOI: 10.1002/anie.200504035
• 发表时间: 2006-03
• 期刊: Angewandte Chemie
• 作者: M. J. Spencelayh;Yaling Cheng;R. Bushby;T. Bugg;Jian-jun Li;P. Henderson;J. O'reilly;S. Evans