Adaptation to climate change in the rhizosphere across the millennia

从AWI的一组独特的古环境样本(北极冰冻土壤和沉积物)及其对应的可追溯到100万年前的古代DNA(ADNA)元基因组开始，我们将检索有关根际生物多样性和功能如何响应气候变化和极端事件的信息。来自该收藏的初步元基因组数据表明，这是一个古老DNA的金矿，代表了根际适应气候变化的时间表。通过重建和分析这些古老的元基因组，并与现有的历史气候变化数据相关联，我们将识别赋予气候耐受性(特别是对高温和干旱的抗性)的分子适应。这将用于i)生产和测试工程根部定植细菌(荧光假单胞菌和绿假单胞菌)，这些细菌将提高植物的气候耐受性(在根部周围产生增湿多糖)，促进在边缘农地(MAL)上生长的能力；ii)为祖先重建耐热和/或耐寒酶以用于工业应用；以及iii)生产为生物生产量身定制的工程恶臭假单胞菌菌株。对于后一种应用，我们将选择编码与气候耐受表型(增湿多糖和生物表面活性剂甜菜碱)相关的生物分子的基因。利用生物技术生产这些分子将是该项目的目标，并将在选定的工业产品中验证它们的应用。目标最终用户应用将包括用于开发3D打印芯片上器官和药物输送系统的多糖和甜菜碱，以及金属加工液、润滑剂和工业清洁产品的配方。

Starting from a unique collection of paleo-environmental samples (frozen Arctic soils and sediments) already at AWI and their corresponding ancient DNA (aDNA) metagenomes that stretch back up to a million years, we will retrieve information on how rhizosphere biodiversity and functionality responded to climate changes and extreme events. Preliminary metagenomic data from the collection suggests it is a gold mine of archaic DNA that represents a timeline of adaptions to climate change in the rhizosphere. By reconstructing and analyzing these ancient metagenomes and correlating with available historical climatic change data, we will identify molecular adaptions that impart climate tolerance (specifically resistance to increased temperature and drought). This will be used to i) produce and test engineered root-colonizing bacteria (Pseudomonas fluorescens and Pseudomonas chlororaphis) that will improve climate tolerance of plants (production of humidifying polysaccharides around the root) facilitating the ability to grow on marginal agricultural land (MAL), ii) inform ancestral reconstruction of thermostable and/or cold tolerant enzymes for industrial application and iii) produce engineered Pseudomonas putida strains tailored for bioproduction. For the latter application, we will select genes that encode biomolecules relevant for climate-tolerant phenotypes (humidifying polysaccharides and the biosurfactant betaines). The production of these molecules using biotechnology will be targeted in the project and their application in selected industrial products verified. Target end-user applications will include polysaccharides and betaines for the development of 3D printed organ-on-chip and drug delivery systems as well as the formulation of metalworking fluids, lubricants and industrial cleaning products.