ppGpp is a bacterial cell size regulator

ppGpp is a bacterial cell size regulator

Büke, F. (TU Delft BN/Greg Bokinsky Lab; Kavli institute of nanoscience Delft; AMOLF)
Grilli, Jacopo (The Abdus Salam International Centre for Theoretical Physics, Trieste)
Cosentino Lagomarsino, Marco (The FIRC Institute of Molecular Oncology; University of Milan)
Bokinsky, G.E. (TU Delft BN/Greg Bokinsky Lab; Kavli institute of nanoscience Delft; University of Milan)
Tans, S.J. (TU Delft BN/Sander Tans Lab; Kavli institute of nanoscience Delft; AMOLF)

2022

Growth and division are central to cell size. Bacteria achieve size homeostasis by dividing when growth has added a constant size since birth, termed the adder principle, by unknown mechanisms.^1,2 Growth is well known to be regulated by guanosine tetraphosphate (ppGpp), which controls diverse processes from ribosome production to metabolic enzyme activity and replication initiation and whose absence or excess can induce stress, filamentation, and small growth-arrested cells.^3–6 These observations raise unresolved questions about the relation between ppGpp and size homeostasis mechanisms during normal exponential growth. Here, to untangle effects of ppGpp and nutrients, we gained control of cellular ppGpp by inducing the synthesis and hydrolysis enzymes RelA and Mesh1. We found that ppGpp not only exerts control over the growth rate but also over cell division and thus the steady state cell size. In response to changes in ppGpp level, the added size already establishes its new constant value while the growth rate still adjusts, aided by accelerated or delayed divisions. Moreover, the magnitude of the added size and resulting steady-state birth size correlate consistently with the ppGpp level, rather than with the growth rate, which results in cells of different size that grow equally fast. Our findings suggest that ppGpp serves as a key regulator that coordinates cell size and growth control.

adder mechanism
cell size
cell size homeostasis
Escherichia coli
growth rate
lineage tree analysis
microfluidics
microscopy
ppGpp
single cell analysis

http://resolver.tudelft.nl/uuid:29a0a526-7c59-4aa1-a80e-b7422823ec64

https://doi.org/10.1016/j.cub.2021.12.033

2023-07-01

0960-9822

Current Biology, 32 (4), 870-877.e5

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2022 F. Büke, Jacopo Grilli, Marco Cosentino Lagomarsino, G.E. Bokinsky, S.J. Tans