W-Health: Tungsten is an Essential Metal for a Healthy Gut Microbiome

项目摘要/摘要 美国国立卫生研究院人类微生物组计划(HMP)彻底改变了我们对人与微生物相互作用的看法 并为研究提供了巨大的推动力，以便更深入地了解 微生物影响人类健康。HMP参考基因组的肠道微生物与人类 胃肠道细菌培养库含142属961种。然而，相对地， 人们对这些微生物知之甚少。在这里，我们将检验一种假设，即金属钨(W) 在生物系统中几乎从未考虑过，对人体肠道微生物群的健康至关重要。我们的 生物信息学分析表明，大量这些肠道微生物含有编码不同种类的基因 含钨氧化还原酶(WOR)家族的成员。只有极少数WOR酶 以前已经被定性，主要来自外来的嗜热微生物。该计划的总体目标 拟议的研究是为了证明WOR家族的其他成员在肠道中具有必要的功能 微生物组。在初步研究中，我们已经表明，一些肠道微生物会摄取微量的W和 他们的含W蠕虫清除肠道中发现的活性和潜在有毒的醛，这些醛是 由熟食和微生物代谢产生。其他含W的蠕虫建议用于 催化其他未知的反应。在拟议的研究中，我们将从系统发育上提纯10个新的 用W-监测(使用电感耦合等离子体质谱)厌氧层析法区分WORS。它们的催化活性和 生理底物将通过酶诱导代谢组学方法(使用LC-MS)确定。 此外，我们认为这些蠕虫中的一些是电子分叉酶，同时 一种新近发现的能量守恒机制--耦合放能和放能反应 生物系统。这一子集的动力学、光谱(使用EPR)和结构(使用CryoEM)分析 将用于研究分叉反应的性质。使用基于基因组的 新陈代谢重建，各种蠕虫的生理功能将被确定，我们将 确定W对肠道微生物新陈代谢的影响，包括对它们对肠道和 与烹饪有关的醛。 相关性：现在很清楚，除了促进消化外，肠道微生物群还在 人类疾病的范围之广，令人惊讶，包括帕金森氏症、精神分裂症、骨关节炎和 心血管疾病和免疫缺陷疾病。拟议研究的结果将提供一个 对我们胃肠道和胃肠道中主要微生物的初级代谢的全新视角 被提议的钨的基本作用，一种被认为很少在生物系统中使用的金属。

Project Summary/Abstract The NIH Human Microbiome Project (HMP) revolutionized our perspective on human-microbe interactions and provided a tremendous impetus for research in order to obtain a much deeper understanding of how microbes impact human health. The gut microorganisms of the HMP Reference Genomes and the Human Gastrointestinal Bacteria Culture Collection contain 961 species representing 142 genera. Yet, relatively little is known about these microorganisms. Herein we will test the hypothesis that tungsten (W), a metal almost never considered in biological systems, is essential for the health of the human gut microbiome. Our bioinformatics analyses reveal that a large number of these gut microbes contain genes encoding diverse members of the W-containing oxidoreductase (WOR) family of enzymes. Only a very few WOR enzymes have been previously characterized, mainly from exotic thermophilic microbes. The overall goal of the proposed research is to show that other members of the WOR family have essential functions in the gut microbiome. In preliminary studies, we have shown that some gut microbes take up trace amounts of W and their W-containing WORs remove reactive and potentially toxic aldehydes found in the gut, which are generated from cooked foods and microbiome metabolism. Other W-containing WORs are proposed to catalyze other as yet unknown reactions. In the proposed research we will purify ten novel phylogenetically distinct WORs by W-monitored (using ICP-MS) anaerobic chromatography. Their catalytic activities and physiological substrates will be determined by an enzyme-induced metabolomics approach (using LC-MS). In addition, we propose that some of these WORs are electron bifurcating enzymes that simultaneously couple exergonic and endergonic reactions, a recently discovered mechanism of energy conservation in biological systems. Kinetic, spectroscopic (using EPR) and structural (using cryoEM) analyses of this subset of W-enzymes will be used to investigate the nature of the bifurcation reactions. Using genome-based metabolic reconstructions, the physiological functions of the various WORs will be ascertained and we will determine the effects of W on the metabolism of the gut microbes, including on their resistance to gut- and cooking-related aldehydes. Relevance: It is now clear that, in addition to facilitating digestion, the gut microbiome plays roles in a surprisingly extensive range of human conditions, including in Parkinson’s, schizophrenia, osteoarthritis and in cardiovascular and immune-deficiency diseases. The results of the proposed research will provide a completely new perspective on the primary metabolisms of the key microbes in our gastrointestinal tract and the proposed essential role of tungsten, a metal that was thought to be seldom used in biological systems.