1u3e

Publication Abstract from PubMed

The structure of I-HmuI, which represents the last family of homing endonucleases without a defining crystallographic structure, has been determined in complex with its DNA target. A series of diverse protein structural domains and motifs, contacting sequential stretches of nucleotide bases, are distributed along the DNA target. I-HmuI contains an N-terminal domain with a DNA-binding surface found in the I-PpoI homing endonuclease and an associated HNH/N active site found in the bacterial colicins, and a C-terminal DNA-binding domain previously observed in the I-TevI homing endonuclease. The combination and exchange of these features between protein families indicates that the genetic mobility associated with homing endonucleases extends to the level of independent structural domains. I-HmuI provides an unambiguous structural connection between the His-Cys box endonucleases and the bacterial colicins, supporting the hypothesis that these enzymes diverged from a common ancestral nuclease.

DNA binding and cleavage by the HNH homing endonuclease I-HmuI.,Shen BW, Landthaler M, Shub DA, Stoddard BL J Mol Biol. 2004 Sep 3;342(1):43-56. PMID:15313606^[1]

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