Graduate Students Mini Symposium VIII 2025

13:15 h Helene Keuthen - MPRG Höfer

NudC-mediated RNA processing and its role in T4 phage infection

Bacteriophages, viruses that infect bacteria, are promising alternatives to antibiotics against multidrug-resistant infections. Their therapeutic development, however, is limited by an incomplete understanding of how phages hijack bacterial gene expression. Recent work highlights the importance of RNA modifications such as NAD caps, which can stabilize RNA transcripts and protect them from nucleases like RNase E. Our lab has established NAD capture sequencing (NAD captureSeq), a method to identify and quantify NAD-capped RNAs during phage infection. This project investigates how Nudix hydrolases influence RNA stability in Escherichia coli during T4 phage infection. We hypothesize that NAD caps may stabilize phage RNA, while Nudix-mediated decapping could act as a bacterial defense by destabilizing viral RNA and restricting phage replication. By comparing NAD-capped RNA profiles in infected E. coli strains, we aim to determine how decapping affects RNA stability using an integrated approach combining NAD captureSeq, transcriptomics, and proteomics. The results will clarify the role of Nudix hydrolases in selective RNA decapping during infection and provide broader insights into phage–host interactions, ultimately informing the development of effective phage-based therapies against resistant bacteria.

13:45 h Hendrik Westedt - AG Erb

The evolutionary origin of Rubisco

The enzyme Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) is responsible
for over 400 gigatons of CO₂ that are fixed annually. Despite the massive interest in the
enzyme, very little is known about how nature managed to evolve such a powerful tool for
carbon fixation. We have been able to shed light on this question by using structural
phylogenetics in combination with ancestral sequence reconstruction and were able to
locate the evolutionary origin of Rubisco.