Our working group is part of an interdisciplinary project with partners coming from a microbiological as well as an engineering background, who are united to tackle the problem of biology’s dark matter. Biology’s dark matter is a term to describe lack of cultivated isolates (Marcy et al., 2007). Whereas genomics reveals an insight into the microbial diversity, fewer than 1% of bacterial organisms actually have been axenically cultivated. But cultivation is vital to understand the function and physiology of microorganisms to the full extent. The MultiKulti project aims to facilitate the process of cultivation with a newly designed bioreactor, the “MultiKulti-reactor”, which is tailored to be a) modular and transportable, b) compatible with modern monitoring and sequencing technologies for frequent controls and management, c) capable of maintaining the in-situ conditions of the microbes of interest and thus, keeping the those alive long-term and d) provide metadata to develop an AI-based cultivation system.

The microbiological MultiKulti-partners focus hereby on different habitats with various microbes of interest to be isolated from i) potable water/ groundwater (TZW, Karlsruhe) ii) a cold-water geyser (UDE, Essen) iii) the marine environment (ICBM, Oldenburg) and iv) from non-extreme environments with focus on polyextremophiles (DLR, Köln).

In the sub-project of our group, we identified Marine Group II Euryarchaeota (MGII) as our microbes of interest, a monophyletic, marine group, which is ubiquitous and particularly abundant in near-surface waters. Despite previous studies on metagenomes, single-cell genomes and ecological studies, the physiology and the function of MGII remains unclear due the lack of an isolate.