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Bacillus subtilis biofilm formation and social interactions

Nature Reviews Microbiology volume 19, pages 600–614 (2021)Cite this article

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Abstract

Biofilm formation is a process in which microbial cells aggregate to form collectives that are embedded in a self-produced extracellular matrix. Bacillus subtilis is a Gram-positive bacterium that is used to dissect the mechanisms controlling matrix production and the subsequent transition from a motile planktonic cell state to a sessile biofilm state. The collective nature of life in a biofilm allows emergent properties to manifest, and B. subtilis biofilms are linked with novel industrial uses as well as probiotic and biocontrol processes. In this Review, we outline the molecular details of the biofilm matrix and the regulatory pathways and external factors that control its production. We explore the beneficial outcomes associated with biofilms. Finally, we highlight major advances in our understanding of concepts of microbial evolution and community behaviour that have resulted from studies of the innate heterogeneity of biofilms.

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Fig. 1: Formation of Bacillus subtilis biofilms in vitro.
Fig. 2: Bacillus subtilis biofilm matrix components and biosynthetic systems.
Fig. 3: Formation of Bacillus subtilis biofilms in the rhizosphere.
Fig. 4: Effects of Bacillus subtilis biofilms in the intestinal tract.
Fig. 5: Evolution of social interactions in Bacillus subtilis biofilms.

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Acknowledgements

Á.T.K was supported by the Danish National Research Foundation (DNRF137) for the Center for Microbial Secondary Metabolites (CeMiSt). Work in the laboratory of N.R.S.-W. is funded by the Biotechnology and Biological Science Research Council (BBSRC) (BB/P001335/1 and BB/R012415/1). N.C.B is funded by a long-term fellowship awarded by the European Molecular Biology Oganization (EMBO) (ALTF 471-2020).

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Nature Reviews Microbiology thanks Y. Chai, I. Kolodkin-Gal and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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  1. These authors contributed equally: Sofia Arnaouteli, Natalie C. Bamford.

Authors and Affiliations

  1. Division of Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee, UK

    Sofia Arnaouteli, Natalie C. Bamford & Nicola R. Stanley-Wall

  2. Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Kongens Lyngby, Denmark

    Ákos T. Kovács

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Arnaouteli, S., Bamford, N.C., Stanley-Wall, N.R. et al. Bacillus subtilis biofilm formation and social interactions. Nat Rev Microbiol 19, 600–614 (2021). https://doi.org/10.1038/s41579-021-00540-9

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