title: Back to the future: the new ICE age.
abstract: The analysis of bacterial genomes has revealed an extraordinary array of conjugal elements (integrative and conjugative element or ICE) that reside in bacterial chromosomes. These elements contribute to the pan-genomes of individual species and confer a wide variety of properties on their bacterial hosts. ICEBs1 is a conjugal element found in Bacillus subtilis that has a remarkable regulatory mechanism that apparently favours conjugation when there are suitable recipient bacteria at high density or when the bacterial host is facing DNA-damaging stresses. In the current issue, Bose et al. dissect the mechanism of induction of transfer of this element, and reveal a new, apparently widespread repressor anti-repressor system and a new mechanism of repressor destruction by proteolysis.
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA. gordon.churchward@emory.edu
authors.forename: Gordon
authors.initials: G
authors.lastname: Churchward