Elucidating and engineering bottromycin biosynthesis

21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，这是由新型抗生素短缺以及在医药和农业中不当使用抗生素造成的。这促使世界卫生组织(WHO)警告称，“采取行动以避免不断发展的全球医疗保健危机的必要性日益迫切”，英国首席医疗官萨莉·戴维斯(Dame Sally Davies)教授宣称，“我们开发新药的速度也不够快”。一种令人难以置信的丰富的抗生素资源是生活在土壤中的微生物，而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生产具有出色抗菌活性的天然产品的能力，因为在竞争营养时，杀死周围细菌的能力是一大优势。我目前正在研究的一种化合物是一种名为博特霉素的抗生素。这种分子具有一些非常不寻常的结构特征，是一种对危险感染非常活跃的抗生素，比如每年导致全球数万人死亡的“超级细菌”MRSA(耐甲氧西林金黄色葡萄球菌)。事实上，人们已经知道博特霉素很多年了，但它的稳定性和可用性问题阻碍了它在临床上的使用。然而，其全新的结构和作用模式使其成为未来非常有希望的抗生素。了解博特霉素的生物合成将为改变这种抗生素的结构并增加其产量所需的途径提供必要的信息。天然产品是由细菌基因组中的基因(DNA)编码的一系列酶(蛋白质)的作用产生的。我之前已经确定了生产博特霉素所需的基因，现在将重点放在每个生化步骤的细节上。我还将开发制造新的博特霉素类化合物的方法。从纯科学的角度来看，这一途径中的生化步骤非常不寻常，了解酶的机制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仪分析生化反应，质谱仪确定化合物的质量并可以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.