ICMCS seminar - Thermodynamic efficiency of E. coli metabolism
ICMCS seminar - Thermodynamic efficiency of E. coli metabolism
- Event time: 4:00pm until 5:00pm
- Event date: 22nd September 2025
- Speaker: Dr Thomas Parton (Max Plank Institute of Colloids and Interfaces)
- Location: James Clerk Maxwell Building (JCMB) 2511 James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB
Event details
Title: Thermodynamic efficiency of E. coli metabolism
Abstract: Unicellular organisms such as Escherichia coli survive and thrive by breaking down high-energy molecules to drive the metabolic processes necessary for growth, division and maintenance. Success in microbial ecosystems requires cells to be able to grow quickly and efficiently on a range of possible substrates. However, cell metabolism is constrained by mass conservation (some of the available carbon must become waste products like CO2 instead of biomass) and the laws of thermodynamics (some of the available free energy must be dissipated instead of being used to perform chemical work). How cells adapt their metabolic processes to satisfy their biological and physical demands is still not fully understood.
In this talk, I will present insights into the thermodynamics of E. coli metabolism from isothermal microcalorimetry of liquid cultures. The high-sensitivity TAM IV microcalorimeter in JCMB allows the heat flow from as little as 106 cells (~1 μW) to be tracked over the growth cycle. Comparing the heat flow during the exponential growth phase of E. coli in different growth media reveals that the switch from aerobic to fully anaerobic respiration occurs at a constant total heat output. This heat matches the value expected for complete combustion of carbon with the available oxygen, suggesting that virtually all the available free energy is dissipated. We also find that the heat produced per biomass created is constant and independent of growth rate, indicating there is a fixed “heat cost” to growth. Correlating the microcalorimetry data with optical density measurements also allows the efficiency of E. coli growth to be quantified, in terms of both carbon and energy use.
Dr Thomas Parton (Max Planck Institute of Colloids and Interfaces)
Dr Jana Schwarz-Linek, Prof Patrick Warren, Dr Aidan Brown, Prof Wilson Poon (University of Edinburgh)
Join Zoom Meeting
https://ed-ac-uk.zoom.us/j/81211470751
Meeting ID: 812 1147 0751
Passcode: ICMCS123
About Condensed Matter lunchtime seminars
This is a weekly series of informal talks given primarily by members of the institute of condensed matter and complex systems, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..