Genetic evidence reveals the indispensable role of the rseC gene for autotrophy and the importance of a functional electron balance for nitrate reduction in Clostridium ljungdahlii

For Clostridium ljungdahlii, the RNF complex plays a key role for energy conversion from gaseous substrates such as hydrogen and carbon dioxide. In a previous study, a disruption of RNF-complex genes led to the loss of autotrophy, while heterotrophy was still possible via glycolysis. Furthermore, it was shown that the energy limitation during autotrophy could be lifted by nitrate supplementation, which resulted in an elevated cellular growth and ATP yield. Here, we used CRISPR-Cas12a to delete: (1) the RNF complex-encoding gene cluster rnfCDGEAB; (2) the putative RNF regulator gene rseC; and (3) a gene cluster that encodes for a putative nitrate reductase. The deletion of either rnfCDGEAB or rseC resulted in a complete loss of autotrophy, which could be restored by plasmid-based complementation of the deleted genes. We observed a transcriptional repression of the RNF-gene cluster in the rseC-deletion strain during autotrophy and investigated the distribution of the rseC gene among acetogenic bacteria. To examine nitrate reduction and its connection to the RNF complex, we compared autotrophic and heterotrophic growth of our three deletion strains with either ammonium or nitrate. The rnfCDGEAB- and rseC-deletion strains failed to reduce nitrate as a metabolic activity in non-growing cultures during autotrophy but not during heterotrophy. In contrast, the nitrate reductase deletion strain was able to grow in all tested conditions but lost the ability to reduce nitrate. Our findings highlight the important role of the rseC gene for autotrophy, and in addition, contribute to understand the connection of nitrate reduction to energy metabolism

Development of the Slow Control for the PANDA-EMC

The Slow Control of the PANDA experiment will be based on EPICS (Experimental Physics and Industrial Control System). EPICS is a set of open source software tools, libraries and applications used worldwide to create distributed real-time control systems for scientific instruments and industrial applications. For the PANDA-EMC the slow control will monitor the temperature, humidity and pressure inside the calorimeter as well as control the power supplies for the read out electronics, crates and the cooling system

Development of the Slow Control for the PANDA-EMC

The Slow Control of the PANDA experiment will be based on EPICS (Experimental Physics and Industrial Control System). EPICS is a set of open source software tools, libraries and applications used worldwide to create distributed real-time control systems for scientific instruments and industrial applications. For the PANDA-EMC the slow control will monitor the temperature, humidity and pressure inside the calorimeter as well as control the power supplies for the read out electronics, crates and the cooling system

Technical Design Report for the: PANDA Straw Tube Tracker

This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM-stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy-loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole \Panda scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described

Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker

<p>This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described.</p>