the C-terminal reductase domain of MubD releases the lipohexapeptide intermediates in an aldehyde form, which enables a spontaneous C-C macrocyclization. In the presence of a thiol group, the macrocyclized MUBs can further undergo spontaneous C-S bond formation and C-C bond cleavage to generate diverse MUB congeners.
含有大环和/或
硫氮杂
环丁烷的变菌素(MUB)及其同类物是来自变形链球菌(龋齿的主要病因)的脂肽。在这里,我们显示MubD的C末端还原酶结构域以醛形式释放脂六肽中间体,这使CC能够自发地大环化。在存在巯基的情况下,大环化的MUB可以进一步自发形成CS键和CC键断裂,从而生成各种MUB同系物。