Trends in Microbiology | Microbe of the Month
Bacillus subtilis
Ákos T. Kovács1,*,@
1
Bacterial Interactions and Evolution Group, DTU Bioengineering, Technical University of Denmark, Søltofts Plads Building 221, Kongens Lyngby 2800, Denmark
KEY FACTS:
Originally named Vibrio subtilis in 1835
by Christian Gottfried Ehrenberg; in 1872
renamed Bacillus subtilis by Ferdinand
Cohn.
First sequenced genome of a Gram-
positive bacterium; single 4.2 Mbp
chromosome with a G+C content of
43%. The genome contains around
4200 genes, though only 253 of them
are essential for cultivation in the
laboratory.
Antibacterial and antifungal activities are
evoked by the bioactive secondary me-
tabolites, including surfactin, plipastatin,
or bacillaene.
It was discovered during the second
World War that B. subtilis can be used to
treat dysentery. Secreted
exopolysaccharides evoke probiotic
properties to prevent disease and in-
flammation by enteric pathogens.
Trends in Microbiology Versatile spreading behavior in the labo-
ratory includes peritrichous flagellum-
Bacillus subtilis became the most studied species in the genus Bacillus due to its natural competence for uptake of dependent single-cell motility and multi-
extracellular DNA that facilitates simple genetic modification and occurrence of sporulation, one of the first studied cellular rafts of swarming cells, in addi-
bacterial cell differentiation processes. The dormant spores can survive harsh circumstances (high temperature, tion to sliding facilitated by
desiccation, UV, and γ-radiation), predation by microorganisms and macroorganisms, or even extraterrestrial con- exopolysaccharide, surfactin, and
ditions. B. subtilis can be isolated from various environments, from soil to marine habitats, and utilized in various hydrophobin.
applications from enzyme production and food fermentation to plant biocontrol. B. subtilis is a model microorgan-
ism for studying cell division, protein secretion, surface motility (swimming, swarming, and sliding), biofilm develop- Its easy cultivation properties and robust
ment, attachment to plant root or fungal hyphae, secondary metabolite production, cytoplasm exchange via secretion machinery make B. subtilis a
intercellular nanotubes, extracellular vesicle release, and kin-discrimination. superior production platform for various
enzymes, generating up to 20–25 g of
proteins per liter of medium. These en-
TAXONOMY AND CLASSIFICATION: zymes are used in dairy, baking, animal
KINGDOM: Bacteria feed, textile, and laundry industries or as
PHYLUM: Firmicutes therapeutics.
ORDER: Bacillales
FAMILY: Bacillaceae Biofilm repellency surpasses the wetta-
GENUS: Bacillus bility of Teflon and is due to the matrix
SPECIES: Bacillus subtilis components, including
Rod-shaped, Gram-positive, catalase-positive, spore-forming exopolysaccharide, amyloid fiber, and a
bacterium small hydrophobin protein, BslA. This
latter surface-active protein could even
delay melting of ice cream.
*Correspondence:
Trends in Microbiology
atkovacs@dtu.dk (Á.T. Kovács).
@
Twitter: @EvolvedBiofilm (Á.T. Kovács)
Trends in Microbiology, Month 2019, Vol. xxx, No. xxx © 2019 Elsevier Ltd. All rights reserved. https://doi.org/10.1016/j.tim.2019.03.008 1
Trends in Microbiology | Microbe of the Month
Acknowledgments
Anna Dragoš (Technical University of Denmark) provided Figure 2. The author wishes to acknowledge the following funding source: Danish National Research Foundation (DNRF137)
for the Center for Microbial Secondary Metabolites.
Literature
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