Our 50th forum session

Resource allocation in individual cells of E. coli during growth transitions

Bacteria adapt to a changing environment by re-distributing their cellular resources (1). A well-established growth law shows a linear relationship between growth rate and the proteome fraction allocated to ribosomes during steady-state growth. This relationship no longer holds during growth transitions, and specific patterns of adaption have been predicted and observed (2, 3). Much less is known, however, about the investment in ribosomes in individual cells. We have measured this quantity during steady-state growth and during growth transitions (4). We observed a large variability in the population and the relationship between growth rate and ribosome concentration no longer follows the population-level growth law. Furthermore, individual cells within a population adopt different strategies for adapting to a changing environment. We will discuss possible causes of this variability and whether it could have a biological function.

References

1. Scott, M. & Hwa, T. Shaping bacterial gene expression by physiological and proteome allocation constraints. Nat. Rev. Microbial. 21, 327-342 (2023).

2. Mori, M., Schink, S., Erickson, D. W., Gerland, U. & Hwa, T. Quantifying the benefit of a proteome reserve in fluctuating environments. Nat. Commun. 8, 1225 (2017).

3. Korea Kohanim, Y., Levi, D., Jona, G., Towbin, B. D., Bren, A. & Alon, U. A bacterial growth law out of steady state. Cell Rep. 23, 2891-2900 (2018).

4. Pavlou, A., Cinquemani, E., Pinel, C., Giordano, N., van Melle-Gateau, M., Mihalcescu, I., Geiselmann, J. & de Jong, H. Single-cell data reveal heterogeneity of investment in ribosomes across a bacterial population Nat. Commun. 16, 285 (2025).

https://www.nature.com/articles/s41467-024-55394-5

Join the Zoom meeting

Please register in advance for this meeting: https://univienna.zoom.us/j/69437528049?pwd=rKVoBfUbMum89lYVMegItXa7InOT4W.1

After registering, you will receive a confirmation email with information on how to join the meeting.