Graduate Students Mini Symposium II 2021


16:00 Francesca Severi, AG Erb

Production of crotonic acid by Methylorubrum extorquens AM1

Methanol is an important feedstock for the chemical industry, and the recent interest in its use for biotechnological purposes has given rise to proposals for a methanol-based bioeconomy.

This project is aimed at engineering Methylorubrum extorquens AM1, a model methylotrophic bacterium, to produce crotonic acid during growth on methanol. For this purpose, we selected a mutant lacking crotonyl-CoA carboxylase/reductase activity, and heterologously expressed the glyoxylate shunt enzymes to allow growth of the strain in the absence of a functional ethylmalonyl-CoA pathway. We subsequently fine-tuned expression by testing several promoters and vectors and applied adaptive laboratory evolution to the most promising strains.

16:30 Nataliya Teteneva, AG Sourjik

Genetic determinants of E. coli survival in lake water

The primary habitat of E. coli is the intestinal tract, and until relatively recently, it was considered not to survive well outside its host. However, it was shown that at least some strains of E. coli can survive and reproduce in soil, water or sand for the long periods of time. But it is not clear yet how these processes are genetically determined.

To find the genetic determinants of E. coli survival in aquatic environments, we performed the genome-wide screen of E. coli survival using the collection of its non-essential knockouts. Additionally, we conducted the screening of several transposon mutant libraries of E. coli including two pathogenic strains. We were able to show that different strains grow and survive in the lake water differently, and determine the number of genes that are important for E. coli survival.

17:00 Sebastian Schaupp, AG Shima

In vitro biosynthesis of the FeGP cofactor

Hydrogenases are complex metalloenzymes, which can catalyse the simplest chemical reaction, the splitting of molecular hydrogen. Three different types of hydrogenases are known, which are categorized based on their active site cofactors as [NiFe]-, [FeFe]- and [Fe]-hydrogenases. The latter of these carries the unique Ironguanylpyridinol (FeGP) cofactor. In order to analyse the biosynthesis of this unique cofactor we have developed an “in vitro biosynthesis” system. This allowed us to proof the presence of a predicted precursor and will enable further analysis of this complex biosynthesis in the future.

Go to Editor View