2lw1

Publication Abstract from PubMed

The bacterial Uup protein belongs to the REG subfamily of soluble ATP-binding cassette (ABC) ATPases, and is implicated in precise excision of transposons. In Escherichia coli, the uup gene encodes a 72kDa polypeptide that comprises two ABC domains, separated by a linker region, and a 12kDa C-terminal domain (CTD). Uup binds double-stranded DNA with no sequence specificity, and we previously demonstrated that the CTD domain is a crucial region that participates in DNA-binding activity. We report herein the NMR structure of Uup CTD, consisting of an intramolecular antiparallel two-stranded coiled coil motif. Structural comparison with analogous coiled coil domains reveals that Uup CTD contains an atypical 3(10)-helix in the alpha-hairpin region that contributes to the hydrophobic core. Using NMR titration experiments, we identified residues of the CTD domain involved in the binding to double-stranded DNA. These residues are located on two opposite surfaces at the base of the coiled coil, formed by the N- and C-terminal extremities, where a strictly conserved proline residue induces an overwinding of the coiled coil. Finally, preliminary analysis of NMR spectra recorded on distinct Uup constructs precludes a fully flexible positioning of the CTD domain in full-length Uup. These structural data are the first reported for a non-ATPase domain within ABC REG subfamily.

The C-terminal domain of the Uup protein is a DNA-binding coiled coil motif.,Carlier L, Sander Haase A, Burgos Zepeda MY, Dassa E, Lequin O J Struct Biol. 2012 Sep 17. pii: S1047-8477(12)00247-X. doi:, 10.1016/j.jsb.2012.09.005. PMID:22995754^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.