A major protein component of the Bacillus subtilis biofilm matrix

@article{Branda2006AMP,
  title={A major protein component of the Bacillus subtilis biofilm matrix},
  author={Steven S. Branda and Frances Chu and Daniel B. Kearns and Richard Losick and Roberto Kolter},
  journal={Molecular Microbiology},
  year={2006},
  volume={59}
}
Microbes construct structurally complex multicellular communities (biofilms) through production of an extracellular matrix. Here we present evidence from scanning electron microscopy showing that a wild strain of the Gram positive bacterium Bacillus subtilis builds such a matrix. Genetic, biochemical and cytological evidence indicates that the matrix is composed predominantly of a protein component, TasA, and an exopolysaccharide component. The absence of TasA or the exopolysaccharide resulted… 
Molecular architecture of the TasA biofilm scaffold in Bacillus subtilis
TLDR
This study explains the previously observed biochemical properties of TasA and shows, for the first time, how a bacterial extracellular globular protein can assemble from monomers into β-sheet-rich fibres, and how such fibres assemble into bundles in biofilms.
The majority of the matrix protein TapA is dispensable for biofilm formation by Bacillus subtilis
TLDR
It is shown that TapA is subjected to proteolytic cleavage in the biofilm and that only the first 57 amino acids of the 253-amino acid protein are required for biofilm architecture, which does not exclude the core conserved region of TapA having a second role beyond that of structuring the B. subtilis biofilm.
The majority of the matrix protein TapA is dispensable for Bacillus subtilis colony biofilm architecture
TLDR
It is shown that TapA is subjected to proteolytic cleavage in the colonyBiofilm and that only the first 57 amino acids of the 253‐amino acid protein are required for colony biofilm architecture, and that proteolysis by these enzymes is not a prerequisite for TapA function.
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TLDR
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TLDR
It is proposed that Veg or a Veg-induced protein acts as an antirepressor of SinR to regulate biofilm formation, and the results of in vivo pulldown assays of the SinR complex indicate that Veg inhibits the interactions between SinR and SlrR.
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TLDR
It is shown that natively synthesized and secreted BslA forms surface layers around the biofilm, and suggests that biofilms formed by other species of bacteria may have evolved similar mechanisms to provide protection to the resident bacterial community.
Dual functionality of the amyloid protein TasA in Bacillus physiology and fitness on the phylloplane
TLDR
It is proposed that, in addition to a structural function during ECM assembly and interactions with plants, TasA contributes to the stabilization of membrane dynamics as cells enter stationary phase.
Bifunctionality of a biofilm matrix protein controlled by redox state
TLDR
It is established that monomeric BSlA is necessary and sufficient to give rise to complex biofilm architecture, whereas dimerization of BslA is required to render the community hydrophobic, and that these roles can be genetically separated through targeted amino acid substitutions.
Extracellular matrix components are required to protect Bacillus subtilis from T6SS-dependent Pseudomonas invasion and modulate co-colonization of plants
TLDR
It is found that the Pseudomonas type VI secretion system (T6SS) is required in the cell-to-cell contact with matrix-impaired B. subtilis cells, revealing a novel role for T6SS against Gram-positive bacteria.
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