3ju0

Publication Abstract from PubMed

The structures of the N-terminal domains of two integrases of closely related but not identical asn tDNA-associated genomic islands, Yersinia HPI (high pathogenicity island; encoding siderophore yersiniabactin biosynthesis and transport) and an Erwinia carotovora genomic island with yet unknown function, HAI7, have been resolved. Both integrases utilize a novel four-stranded beta-sheet DNA-binding motif, in contrast to the known proteins that bind their DNA targets by means of three-stranded beta-sheets. Moreover, the beta-sheets in Int(HPI) and Int(HAI7) are longer than those in other integrases, and the structured helical N terminus is positioned perpendicularly to the large C-terminal helix. These differences strongly support the proposal that the integrases of the genomic islands make up a distinct evolutionary branch of the site-specific recombinases that utilize a unique DNA-binding mechanism.

Structures of the arm-type binding domains of HPI and HAI7 integrases.,Szwagierczak A, Antonenka U, Popowicz GM, Sitar T, Holak TA, Rakin A J Biol Chem. 2009 Nov 13;284(46):31664-71. Epub 2009 Sep 8. PMID:19737930^[1]

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