5TMX

Solution Structure of SinI, antagonist to the master biofilm-regulator SinR in Bacillus subtilis


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

The Solution Structures and Interaction of SinR and SinI: Elucidating the Mechanism of Action of the Master Regulator Switch for Biofilm Formation in Bacillus subtilis.

Milton, M.E.Draughn, G.L.Bobay, B.G.Stowe, S.D.Olson, A.L.Feldmann, E.A.Thompson, R.J.Myers, K.H.Santoro, M.T.Kearns, D.B.Cavanagh, J.

(2019) J Mol Biol 

  • DOI: https://doi.org/10.1016/j.jmb.2019.08.019
  • Primary Citation of Related Structures:  
    5TMX, 5TN0, 5TN2

  • PubMed Abstract: 

    Bacteria have developed numerous protection strategies to ensure survival in harsh environments, with perhaps the most robust method being the formation of a protective biofilm. In biofilms, bacterial cells are embedded within a matrix that is composed of a complex mixture of polysaccharides, proteins, and DNA. The gram-positive bacterium Bacillus subtilis has become a model organism for studying regulatory networks directing biofilm formation. The phenotypic transition from a planktonic to biofilm state is regulated by the activity of the transcriptional repressor, SinR, and its inactivation by its primary antagonist, SinI. In this work, we present the first full-length structural model of tetrameric SinR using a hybrid approach combining high-resolution solution nuclear magnetic resonance (NMR), chemical cross-linking, mass spectrometry, and molecular docking. We also present the solution NMR structure of the antagonist SinI dimer and probe the mechanism behind the SinR-SinI interaction using a combination of biochemical and biophysical techniques. As a result of these findings, we propose that SinI utilizes a residue replacement mechanism to block SinR multimerization, resulting in diminished DNA binding and concomitant decreased repressor activity. Finally, we provide an evidence-based mechanism that confirms how disruption of the SinR tetramer by SinI regulates gene expression.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein SinI
A, B
63Bacillus subtilis subsp. subtilis str. 168Mutation(s): 0 
Gene Names: sinIBSU24600
UniProt
Find proteins for P23308 (Bacillus subtilis (strain 168))
Explore P23308 
Go to UniProtKB:  P23308
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP23308
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesRO1-GM055769

Revision History  (Full details and data files)

  • Version 1.0: 2017-10-25
    Type: Initial release
  • Version 1.1: 2019-10-09
    Changes: Data collection, Database references
  • Version 1.2: 2019-12-25
    Changes: Author supporting evidence
  • Version 1.3: 2023-06-14
    Changes: Database references, Other
  • Version 1.4: 2024-05-15
    Changes: Data collection, Database references