Deciphering the steps of prodiginine biosynthesis

描述(申请人提供)：Prodiginines是由放线菌和其他真细菌产生的线性和环状低聚吡咯红色色素抗生素家族。这类抗生素的成员已经知道一段时间了，因为它们具有广泛的抗真菌和抗菌活性。近年来，人们对这些天然产品产生了极大的兴趣，因为它们似乎具有显著的抗疟疾、抗癌和免疫抑制活性。我们利用一系列的遗传和生化实验揭示了天蓝色链霉菌基因组中的一组23个红色基因编码了一条迷人的和不寻常的途径，导致了十一烷基赖氨酸和环化的衍生物链霉菌B的形成。这个过程的初始阶段涉及到与脂肪酸生物合成的复杂界面，这将在特定目标1中进一步研究。随后的阶段涉及许多具有异常结构和催化活性的多功能和单功能蛋白质，特定目标2-4将是我们对这些研究的继续。我们的初步工作还表明，我们可以通过将途径中间产物的类似物喂给适当的阻断突变体，或创建杂交生物合成途径(将Red蛋白质与催化活性相似但底物特异性不同的蛋白质交换)，在天蓝色链霉菌中产生新的环状和线状prodiginine类似物。具体目标5将在这些成功的基础上产生更多新的前列腺素结构，并在抗疟疾、免疫抑制、抗癌和抗真菌试验中评估它们的生物活性。广泛的化学、遗传和生化方法将用于这5个具体目标，以满足我们的长期目标：a)建立对前列腺素生物合成途径的酶学的全面了解，以及b)利用这些知识来产生新的线型和环型前列腺素结构，以用于潜在的人类健康应用。分层语言描述。一些细菌产生鲜红色的色素(Prodiginine)，这种色素在许多人类健康应用中都有希望，包括治疗癌症、抗击疟疾和其他传染病，以及帮助器官移植患者。这项工作将确定这些前列腺素是如何由细菌产生的，并利用这一知识来产生和鉴定具有正确化学性质和生物活性的新的前列腺素，用于可能的临床开发。

DESCRIPTION (provided by applicant): Prodiginines are a family of linear and cyclic oligopyrrole red-pigmented antibiotics produced by actinomycetes and other eubacteria. Members of this class of antibiotics have been known for some time, as have their broad antifungal, antibacterial activity. There has been a dramatic interest in recent years in these natural products as they appear to have pronounced antimalarial, anticancer and immunosuppressant activity. We have used a series of genetic and biochemical experiments to reveal that a cluster of 23 red genes in Streptomyces coelicolor genome encode a fascinating and unusual pathway leading to formation of undecylprodiginine and a cyclized derivative, streptorubin B. The initial stages of this process involve a complex interface with fatty acid biosynthesis which will be further investigated in specific aim 1. Subsequent stages involve numerous multifunctional and monofunctional proteins with unusual architecture and catalytic activities and specific aims 2-4 will be a continuation of our studies on these. Our preliminary work has also demonstrated that we can generate novel cyclic and linear prodiginine analogues in S. coelicolor by either feeding analogues of pathway intermediates to the appropriate blocked mutants, or creation of hybrid biosynthetic pathways (exchanging Red proteins with proteins of similar catalytic activity but different substrate specificities). Specific aim 5 will build on these successes generating additional novel prodiginine structures and evaluating their biological activity in antimalarial, immunosuppressant, anticancer and antifungal assays. A wide array of chemical, genetic and biochemical approaches will be used for these 5 specific aims which address our long term objective of a) building a comprehensive understanding of the enzymology of prodiginine biosynthetic pathways and b) using this knowledge to generate novel linear and cyclic prodiginines structures for potential application in human health. Lay Language Description. Some bacteria produce bright red pigments (prodiginines) which show promise for numerous human health applications including cancer treatment, fighting malaria and other infectious diseases, and helping organ transplant patients. This work will identify how these prodiginines are made by the bacteria and use this knowledge to generate and identify new prodiginines with the correct chemical properties and biological activities for possible clinical development.