5D17

Structure of the C-terminal domain of TnsE at 2.85 resolution

Summary for 5D17

• Entry DOI: 10.2210/pdb5d17/pdb
• Related: 5D16
• Descriptor: Transposon Tn7 transposition protein TnsE (2 entities in total)
• Functional Keywords: transposition, tn7, dna binding proteins, conformational toggle, dna binding protein
• Biological source: Escherichia coli
• Total number of polymer chains: 12
• Total formula weight: 278791.33

Authors

Guarne, A.,Caron, J.J. (deposition date: 2015-08-03, release date: 2015-09-30, Last modification date: 2024-10-23)

Primary citation

Shi, Q.,Straus, M.R.,Caron, J.J.,Wang, H.,Chung, Y.S.,Guarne, A.,Peters, J.E.
Conformational toggling controls target site choice for the heteromeric transposase element Tn7.
Nucleic Acids Res., 43:10734-10745, 2015

PubMed Abstract: The bacterial transposon Tn7 facilitates horizontal transfer by directing transposition into actively replicating DNA with the element-encoded protein TnsE. Structural analysis of the C-terminal domain of wild-type TnsE identified a novel protein fold including a central V-shaped loop that toggles between two distinct conformations. The structure of a robust TnsE gain-of-activity variant has this loop locked in a single conformation, suggesting that conformational flexibility regulates TnsE activity. Structure-based analysis of a series of TnsE mutants relates transposition activity to DNA binding stability. Wild-type TnsE appears to naturally form an unstable complex with a target DNA, whereas mutant combinations required for large changes in transposition frequency and targeting stabilized this interaction. Collectively, our work unveils a unique structural proofreading mechanism where toggling between two conformations regulates target commitment by limiting the stability of target DNA engagement until an appropriate insertion site is identified.

PubMed: 26384427
DOI: 10.1093/nar/gkv913

Experimental method

X-RAY DIFFRACTION (2.85 Å)