Methanogenic Archaea

Methanogenic archaea (methanogens) are the major biological source of the greenhouse gas methane. They exist in and are adapted to a wide range of anoxic ecosystems.

We combine computational microbiology, laboratory cultivation, molecular and protein biochemical techniques to illuminate genetic features that are predicted to shape methanogen adaptability and ultimately methane production.

Projects:

Functional role of nucleotide tandem repeats in genomes of methanogens

Tandem repeats in methanogens have been characterized using computational approaches, and their potential functions in proteins and as regulatory RNAs is being investigated using the model methanogen Methanosarcina mazei. — Tandem repeats in methanogens have been characterized using computational approaches, and their potential functions in proteins and as regulatory RNAs is being investigated using the model methanogen *Methanosarcina mazei*.

Recently, pervasive nucleotide tandem repeats (TRs) have been uncovered in the genomes of methanogens. These TRs are hypothesized to impact methanogen physiology and metabolism, possibly representing an overlooked feature explaining methanogens ecological adaptability and resilience. Our research aims to uncover the functional roles of TRs in archaeal proteins and to investigate the regulatory potential of intergenic TRs in controlling gene expression.

Project leader: Sebastian Haiß

The Epigenetics of Methanogens

Nanopore-based epigenomics of methanogenic archaea: Long-read sequencing of model methanogens aims to reveal DNA methylation patterns involved in gene regulation, potentially uncovering a previously underexplored regulatory layer in biological methane production and other key processes. Created with BioRender.com

We use Nanopore sequencing of model methanogenic archaea to uncover epigenetic patterns involved in self-identification and gene regulation, providing insights into a new regulatory dimension of biological methane production.

Project Leader: Jo Herbert

Production and Characterization of Borg Proteins in Methanosarcina mazei Gö1

From environment to function: discovery, cloning, and heterologous expression of Borg genes leading to production and characterization of Borg proteins in Methanosarcina mazei. — From environment to function: discovery, cloning, and heterologous expression of Borg genes leading to production and characterization of Borg proteins in *Methanosarcina mazei*. Created with BioRender.com

Borgs are recently discovered extrachromosomal elements that are predicted to be associated with the anaerobic methanotrophic archaeon "Candidatus Methanoperedens". These giant linear DNA elements encode various metabolic and structural proteins and are predicted to augment methane oxidation by their host. The absence of Borgs in any laboratory cultures so far deems it difficult to characterize them experimentally. In this project, we aim to express Borg proteins in methanogens using Methanosarcina mazei Gö1 as a model system to gain first experimental insights into Borg biology, while advancing genetic engineering approaches of methanogens.

Project leader: Akshay Joshi