Adaptation to climate change in the rhizosphere across the millennia

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.