1b69

Publication Abstract from PubMed

The integrase protein catalyzes the excision and integration of the Tn916 conjugative transposon, a promiscuous genetic element that spreads antibiotic resistance in pathogenic bacteria. The solution structure of the N-terminal domain of the Tn916 integrase protein bound to its DNA-binding site within the transposon arm has been determined. The structure reveals an interesting mode of DNA recognition, in which the face of a three-stranded antiparallel beta-sheet is positioned within the major groove. A comparison to the structure of the homing endonuclease I-Ppol-DNA complex suggests that the three-stranded sheet may represent a new DNA-binding motif whose residue composition and position within the major groove are varied to alter specificity. The structure also provides insights into the mechanism of conjugative transposition. The DNA in the complex is bent approximately 35 degrees and may, together with potential interactions between bound integrase proteins at directly repeated sites, significantly bend the arms of the transposon.

NMR structure of the Tn916 integrase-DNA complex.,Wojciak JM, Connolly KM, Clubb RT Nat Struct Biol. 1999 Apr;6(4):366-73. PMID:10201406^[1]

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