Elucidating and engineering bottromycin biosynthesis

世纪对公众健康的最大威胁之一是多重耐药细菌感染的增加，这是由于新型抗生素的短缺以及在医学和农业中抗生素的不当使用造成的。这促使世界卫生组织警告说，“采取行动避免全球医疗危机的必要性越来越紧迫”，英国首席医疗官Dame Sally Davies教授宣布，“我们开发新药的速度也不够快”。一种非常丰富的抗生素资源是生活在土壤中的微生物，大多数临床使用的抗生素来自这些细菌。这些细菌已经进化出产生具有优异抗菌活性的天然产物的能力，因为在争夺营养时，杀死周围细菌的能力是一个很大的优势。我目前正在研究的一种化合物是一种名为bottromycin的抗生素。这种分子具有一些非常不寻常的结构特征，是一种非常有效的抗生素，可以对付像“超级细菌”MRSA（耐甲氧西林金黄色葡萄球菌）这样的危险感染，每年在全世界造成数万人死亡。博曲霉素实际上已经知道很多年了，但是其稳定性和可用性的问题阻止了它在临床上的使用。然而，其全新的结构和作用方式使其成为未来极具前景的抗生素。对博曲霉素生物合成的了解将提供必要的信息，以修改该途径，改变这种抗生素的结构，并增加产量。天然产物是通过一系列酶（蛋白质）的作用产生的，这些酶由细菌基因组中的基因（DNA）编码。我以前已经确定了生产博曲霉素所需的基因，现在将重点关注每个生化步骤的细节。我还将开发新的类似博特霉素的化合物。从纯科学的角度来看，这个途径中的生化步骤是非常不寻常的，对酶机制的理解将增加我们对酶功能的理解。这项工作涉及的实验技术包括细菌培养物的发酵、酶的纯化和使用质谱法分析生化反应，质谱法确定化合物的质量并可提供重要的结构信息。

One of the greatest threats to public health in the 21st century is the rise of multi-drug resistant bacterial infections, which has been caused by a shortage in new types of antibiotics, as well as the improper use of antibiotics in medicine and agriculture. This has prompted the World Health Organisation to warn that "the need for action to avert a developing global crisis in health care is increasingly urgent" and the UK's Chief Medical Officer, Prof. Dame Sally Davies, to declare that "we are also not developing new drugs fast enough". One incredibly rich resource for antibiotics are microorganisms that live in soil, and the majority of clinically used antibiotics come from these bacteria. These bacteria have evolved the ability to produce natural products with excellent antibacterial activities, as the ability to kill surrounding bacteria is a big advantage when competing for nutrients.One compound I am currently researching is an antibiotic called bottromycin. The molecule has some highly unusual structural features and is a very active antibiotic towards dangerous infections like the "superbug" MRSA (methicillin-resistant Staphylococcus aureus), which kills tens of thousands of people worldwide each year. Bottromycin has actually been known for many years but problems with its stability and availability have prevented it from being used clinically. However, its entirely novel structure and mode of action make it highly promising antibiotic of the future. An understanding of bottromycin biosynthesis would provide the information necessary for the pathway to be modified to alter the structure of this antibiotic and increase the amount that can be made.Natural products are produced by the action of a series of enzymes (proteins), which are encoded by genes (DNA) in the bacterial genome. I have previously identified the genes required for bottromycin production and will now focus on the details of each biochemical step. I will also develop methods to make new bottromycin-like compounds. From a purely scientific perspective, the biochemical steps in this pathway are highly unusual, and an understanding of the enzyme mechanisms will increase our understanding of enzyme function. The experimental techniques involved in this work include the fermentation of bacterial cultures, the purification of enzymes and the analysis of biochemical reactions using mass spectrometry, which determines the mass of a compound and can provide important structural information.