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Protein post-translational modifications in bacteria

Abstract

Over the past decade the number and variety of protein post-translational modifications that have been detected and characterized in bacteria have rapidly increased. Most post-translational protein modifications occur in a relatively low number of bacterial proteins in comparison with eukaryotic proteins, and most of the modified proteins carry low, substoichiometric levels of modification; therefore, their structural and functional analysis is particularly challenging. The number of modifying enzymes differs greatly among bacterial species, and the extent of the modified proteome strongly depends on environmental conditions. Nevertheless, evidence is rapidly accumulating that protein post-translational modifications have vital roles in various cellular processes such as protein synthesis and turnover, nitrogen metabolism, the cell cycle, dormancy, sporulation, spore germination, persistence and virulence. Further research of protein post-translational modifications will fill current gaps in the understanding of bacterial physiology and open new avenues for treatment of infectious diseases.

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Fig. 1: Protein modifications in bacteria.
Fig. 2: Phosphorylation, lysine acetylation and succinylation.
Fig. 3: The prokaryotic ubiquitin-like protein (Pup)–proteasome system.
Fig. 4: Role of Hanks-type kinases in cell division and morphogenesis and developmental behaviours.
Fig. 5: Summary of known bacterial PTMs and their involvement in cellular physiology.

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Acknowledgements

The authors thank A. Velic, P. Spät and M. Semanjski for help with the preparation of the manuscript. B.M. was supported by grants from the Deutsche Forschungsgemeinschaft (German Research Foundation Cluster of Excellence EXC 2124, SFB 766, FOR 2816, TRR 261) and the German–Israeli Foundation (I-1464–416.13/2018). I.M. was supported by grants from the Swedish Research Council and the Novo Nordisk Foundation (NNF10CC1016517). K.F. was supported by grants from the Deutsche Forschungsgemeinschaft (EXC 2124, SFB 766, GRK 1708, FOR 2816). C.G. was supported by grants from the CNRS, the ANR (ANR-15-CE32–01, ANR-18-CE11–0017–02) and the Bettencourt Schueller Foundation. E.W.-B. was supported by the Swiss National Science Foundation (31003A, 163314).

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B.M. researched data for the article, designed the outline and reviewed and edited the manuscript before submission. B.M., K.F., J.H, E.W.-B., C.G. and I.M. contributed substantially to the discussion of the content and wrote the article.

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Correspondence to Boris Macek.

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Glossary

Phosphoproteome

All proteins of an organism, tissue or a cell that contain at least one phosphate group.

Two-component systems

(TCS). Stimulus–response coupling mechanisms that enable organisms to sense and respond to changes in different environmental conditions. They typically consist of a membrane-bound histidine kinase that senses a specific environmental stimulus and a corresponding response regulator that mediates the cellular response.

Sirtuin

Protein deacetylases that couple lysine deacetylation to NAD hydrolysis, yielding O-acetyl-ADP-ribose, the deacetylated substrate and nicotinamide.

Fruiting bodies

Aerial structures composed of aligned chains of attached Bacillus subtilis cells that function as preferential sites for sporulation.

Divisome

A contractile ring of proteins forming around the circumference of the midpoint of the cell at the time of division and mediating the formation of a septum.

Muropeptides

Polymers of glycan and peptides found in bacterial cell walls (also termed ‘peptidoglycans’).

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Macek, B., Forchhammer, K., Hardouin, J. et al. Protein post-translational modifications in bacteria. Nat Rev Microbiol 17, 651–664 (2019). https://doi.org/10.1038/s41579-019-0243-0

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