Targeted Proteomic Approaches for Natural Product Biosynthetic Pathway Discovery

天然产物生物合成途径发现的靶向蛋白质组学方法

• 批准号: 9203060
• 负责人: KRISTINA HAKANSSON
• 金额: $ 28.1万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-02-01 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9203060
• 关键词: 4' -phosphopantetheine; Acyl Carrier Protein; Alkylation; Amino Acids; Anabolism; Antibiotics; Antineoplastic Agents; Antitoxins; Asthma; Bacteria; Biochemical; Bioinformatics; Biological Models; Biosynthetic Proteins; Brevenal; Carbohydrates; Carbon Dioxide; Carrier Proteins; Cells; Cessation of life; Chemicals; Clinical; Clinical Treatment; Clinical Trials; Collaborations; Complex; Crosslinker; Cystic Fibrosis; DNA; Data; Data Set; Dehydration; Detection; Development; Dimensions; Dinophyceae; Dissociation; Ecteinascidin 743; Electron Transport; Electrons; Engineering; Environment; Enzymes; Florida; Fourier transform ion cyclotron resonance; Gases; Gene Cluster; Generations; Genome; Health; Human; Human Genome; Hybrids; In Vitro; Ions; Irritants; Knowledge; Lasers; Link; Marine Invertebrates; Marines; Mass Spectrum Analysis; Methods; Mining; Modification; Molecular Weight; Multienzyme Complexes; Natural Products; Organism; Pathway interactions; Peptides; Pharmaceutical Preparations; Phase; Phosphopeptides; Plankton; Plants; Positioning Attribute; Post-Translational Protein Processing; Process; Prosthesis; Proteins; Proteome; Proteomics; Reaction; Research; Research Personnel; Sampling; Serine; Shotguns; Source; Streptomyces; Structure; Sulfhydryl Compounds; System; Therapeutic; United States; Urochordata; absorption; base; bioactive natural products; biosynthetic product; brevetoxin; drug discovery; drug production; enzyme mechanism; experience; genome sequencing; human disease; improved; innovation; inorganic phosphate; interest; link protein; metaproteomics; microbial; novel; novel strategies; overexpression; peptide drug; peptide synthase; picromycin; polyketide synthase; polypeptide; protein expression; public health relevance; reconstitution; red tide; respiratory; whole genome

DESCRIPTION (provided by applicant): Natural products from organisms as diverse as bacteria, plants, and marine invertebrates constitute a rich source of molecules with wide-ranging bioactivities related to human disease, including antibiotics and anti- cancer agents. A plentitude of these structurally complex secondary metabolites are synthesized by large enzyme complexes, polyketide synthases (PKSs) and/or nonribosomal peptide synthetases (NRPSs), in a linear "assembly-line" manner. PKSs/NRPSs consist of multiple polypeptides (modules), each with multiple functional domains that covalently load appropriate building blocks (e.g., malonyl groups for PKSs and activated amino acids for NRPSs) and sequentially condense them onto the growing natural product chain. Often, additional enzymes are involved for further processing, such as attachment of carbohydrates. There is also enzymatic variety within each module such that, e.g., dehydration, reduction, and alkylation reactions may occur at any position in the growing natural product chain for increased structural diversity. Tremendous advances in our understanding of natural product biosynthetic pathways are beginning to allow pathway engineering for generation of compounds with new or improved bioactivities. However, in many cases, valuable natural products are known but the corresponding biosynthetic pathways remain undiscovered due to, e.g., challenges in genome sequencing. For such systems, pathway discovery at the protein rather than DNA level is emerging as an attractive approach that also verifies biosynthetic protein expression. However, due to the complexity of collected metaproteomic samples, targeted methods are needed. This proposal describes the development of innovative methods for targeted PKS/NRPS proteomics, as well as their application for pathway discovery in the dinoflagellate Karenia brevis. This marine plankton produces the highly structurally complex brevetoxins, responsible for the deaths and illnesses associated with the Florida red tide, as well as the antitoxin, brevenal, currently in clinical trils for treatment of asthma and cystic fibrosis. We will harness the high infrared absorption of phosphopantetheine (Ppant) prosthetic groups on PKSs/NRPSs to selectively detect Ppant-containing peptides in proteolytic digests with mass spectrometry in a parallel rather than the conventional sequential manner. This innovative strategy will be validated in highly complex metaproteomic samples such as the tunicate/microbial symbiont producer of the approved anti-cancer agent ET-743, for which we recently demonstrated feasibility of biosynthetic protein detection. We will also develop suitable bioinformatic approaches for automated mining of such complex datasets. For increased selectivity, we will develop IR-active chemical probes, resembling secondary metabolite biosynthetic intermediates, for loading onto PKSs/NRPSs. These approaches will be applied for PKS discovery in collected K. brevis samples. Biosynthetic pathway identification will allow characterization of the corresponding undoubtedly highly intricate biosynthetic mechanisms, and provide a gateway to sustainable drug production.

描述（由申请人提供）：来自细菌、植物和海洋无脊椎动物等多种生物的天然产物构成了具有与人类疾病相关的广泛生物活性的分子的丰富来源，包括抗生素和抗癌剂。这些结构复杂的次级代谢产物的一部分是由大的酶复合物，聚酮酶（PKS）和/或非核糖体肽合成酶（NRPS），以线性的“装配线”的方式合成的。PKS/NRPS由多个多肽（模块）组成，每个多肽具有多个功能结构域，所述功能结构域共价负载适当的结构单元（例如，PKS的丙二酰基和NRPS的活化氨基酸），并将它们依次缩合到生长的天然产物链上。通常，额外的酶参与进一步加工，例如碳水化合物的附着。在每个模块内还存在酶种类，使得例如，脱水、还原和烷基化反应可在生长的天然产物链中的任何位置发生，以增加结构多样性。 我们对天然产物生物合成途径的理解取得了巨大进展，开始允许途径工程产生具有新的或改进的生物活性的化合物。然而，在许多情况下，有价值的天然产物是已知的，但相应的生物合成途径仍然未被发现，这是由于，例如，基因组测序的挑战。对于这样的系统，在蛋白质而不是DNA水平的途径发现正在成为一种有吸引力的方法，也验证了生物合成蛋白质的表达。然而，由于收集的元蛋白质组学样品的复杂性，需要有针对性的方法。该提案描述了靶向PKS/NRPS蛋白质组学的创新方法的发展，以及它们在甲藻Karenia brevis中的通路发现的应用。这种海洋浮游生物产生结构高度复杂的短尾藻毒素，导致与佛罗里达赤潮有关的死亡和疾病，以及抗毒素短尾藻醛，目前在临床试验中用于治疗哮喘和囊性纤维化。 我们将利用PKS/NRPS上磷酸泛酰巯基乙胺（Ppant）辅基的高红外吸收，以平行而不是传统的顺序方式用质谱法选择性地检测蛋白水解酶中含有Ppant的肽。这种创新策略将在高度复杂的元蛋白质组学样品中得到验证，例如批准的抗癌剂ET-743的被囊/微生物共生体生产者，我们最近证明了生物合成蛋白质检测的可行性。我们还将开发合适的生物信息学方法来自动挖掘这些复杂的数据集。为了提高选择性，我们将开发IR活性化学探针，类似于次级代谢物生物合成中间体，用于加载到PKS/NRPS上。这些方法将应用于收集的K. brevis样本。生物合成途径鉴定将允许表征相应的无疑是高度复杂的生物合成机制，并提供了一个可持续的药物生产的门户。