Polymyxins are used as the last-line therapy against multidrug-resistant bacteria. However, their further clinical development needs to solve problems related to the presence of heterogeneous analogs, but there is still no platform or methods that can regulate the biosynthesis of polymyxin analogs. In this study, we present an approach to swap domains in the polymyxin gene cluster to regulate the production of different analogs. Following adenylation domain swapping, the proportion of polymyxin B1 increased from 41.36 to 52.90%, while that of B1-1 decreased from 18.25 to 3.09%. The ratio of polymyxin B1 and B3 following starter condensation domain swapping changed from 41.36 and 16.99 to 55.03 and 6.39%, respectively. The two domain-swapping strains produced 62.96% of polymyxin B1, 6.70% of B3 and 3.32% of B1-1. This study also revealed the presence of overflow fluxes between acetoin, 2,3-butanediol and polymyxin. To our best knowledge, this is the first report of engineering the polymyxin synthetase gene cluster in situ to regulate the relative proportions of polymyxin analogs. This research paves a way for regulating lipopeptide analogs and will facilitate the development of novel lipopeptide derivatives.

多粘菌素被用作抗多药耐药细菌的最后治疗方法。然而，他们的进一步临床开发需要解决与异质类似物的存在有关的问题，但是仍然没有平台或方法可以调节多粘菌素类似物的生物合成。在这项研究中，我们提出了一种方法来交换多粘菌素基因簇中的域，以调节不同类似物的产生。腺苷酸化域交换后，多粘菌素B1的比例从41.36增加到52.90％，而B1-1的比例从18.25减少到3.09％。起始缩合域交换后多粘菌素B1和B3的比例分别从41.36和16.99变为55.03和6.39％。两个域交换菌株产生了62.96％的多粘菌素B1，B70的6.70％和B1-1的3.32％。这项研究还揭示了在乙醛，2，3-丁二醇和多粘菌素之间存在溢流。据我们所知，这是第一个原位改造多粘菌素合成酶基因簇以调节多粘菌素类似物相对比例的报道。这项研究为调节脂肽类似物铺平了道路，并将促进新型脂肽衍生物的开发。