Discovery and characterization of new natural products from uncultured bacteria

描述（由申请人提供）：生物活性天然产物的研究是鉴定具有独特细胞靶点的化合物的非常有效的途径，所述化合物既可用作治疗剂，又可用作复杂生物系统的调节剂，最近在化学遗传学的新兴领域中。对环境样品进行分子系统发育分析的关键启示之一是，环境中只有一小部分细菌容易培养。因此，用于发现新的天然产品的传统方法不可能提供获取自然界中存在的绝大多数天然产品的途径。尚未培养的土壤微生物，因此没有被检查用于生产有用的天然产物，其数量至少比培养的微生物多两到三个数量级。使用PCR与简并引物的基础上的保守区域的基因已知参与天然产物的生物合成和高通量测序，我们建议筛选直接从土壤中提取的DNA的粘粒文库的生物合成途径，编码新的天然产物的生产。然后，异源表达将用于获得由这些新基因簇编码的分子，并在各种人类疾病相关筛选中筛选所得分子的生物活性。相关性：天然产品，天然衍生的小有机化合物，传统上是FDA批准的治疗药物的主要来源之一。未培养的细菌是最大的遗传多样性的剩余池之一，尚未被检查的次级代谢产物的生产。开发方法，以功能性地访问以前无法访问的天然产物产生的未培养的细菌应显着增加的数量和多样性的天然产物，可用于测试作为探针的生物过程和治疗剂。

DESCRIPTION (provided by applicant): The study of biologically active natural products has been a very effective gateway to the identification of compounds with unique cellular targets that have been useful both as therapeutics and, more recently in the emerging field of chemical genetics, as modulators of complex biological systems. One of the key revelations to come from molecular phylogenetic analyses of environmental samples is that only a small fraction of bacteria present in the environment is easily cultured. Traditional approaches used for the discovery of new natural products are therefore unlikely to provide access to the vast majority of natural products that exist in nature. Soil microbes that have not yet been cultured and as a result have not been examined for the production of useful natural products outnumber their cultured counterparts by at least two to three orders of magnitude. Using PCR with degenerate primers based on conserved regions in genes known to be involved in the biosynthesis of natural products and high throughput sequencing we are proposing to screen cosmid libraries of DNA extracted directly from soil for biosynthetic pathways that encode the production of new natural products. Heterologous expression will then be used to access the molecules encoded by these new gene clusters and the resulting molecules screened for biological activity in a variety of human disease related screens. Relevance: Natural products, naturally derived small organic compounds, have traditionally been one of the major sources of FDA approved therapeutics. Uncultured bacteria are one of the largest remaining pools of genetic diversity that have not yet been examined for the production of secondary metabolites. The development of methods to functionally access the previously inaccessible natural products produced by uncultured bacteria should significantly increase the number and diversity of natural products that are available to test as probes of biological processes and therapeutic agents.