Jonathan did his biochemistry undergraduate at university of Bayreuth working in the lab of Benedikt Westermann on mitochondrial fusion and fission. In 2008, he started his PhD at the Max-Planck-Institute of molecular cell biology and genetics. He joined the lab of the late Suzanne Eaton studying the role of systemically circulating Hedgehog and steroid hormone signaling during fruit fly development. As a postdoc, Jonathan moved to New Haven joining the Neugebauer lab at Yale university. His research focused on establishing approaches to the quantitatively measure the flows of energy in biological systems, and to investigate the metabolism and energetics costs of development. Since 2021, Jonathan is a group leader at MPI-CBG working on the energetics of biological systems.
Tuesday April 18th
Energetics of Biological Systems
Living biological systems are metabolically active, open systems that constantly exchange matter and energy with their environment. They function out of equilibrium and use metabolic pathways to obtain energy from chemical bonds derived from nutrients to fulfill the system's energetic requirements. To understand how cells and organisms function, we need to determine how metabolic energy is partitioned among the complex array of cellular processes that are necessary for life at any scale, from isolated biochemical networks to quiescent and highly proliferative cells to organismal growth and development. To investigate the energetics of biological systems, we use isothermal calorimetry to quantitatively measure the flow of energy in form of heat between biological systems and their surroundings. Focusing on cleavage stage development of zebrafish embryos, we show that the heat dissipation rate increased over time and with cell number. Unexpectedly, we found that the heat dissipation rate oscillated with periods matching the synchronous early embryonic cell cycle. By combining these measurements with perturbations, imaging, metabolomics and theory, we will show that the energetic costs and metabolic changes associated with a given biological process can be estimated, and thus, provides a means towards understanding the energetics and possible constraints of biological systems.