Conformational transitions during FtsK translocase activation of individual XerCD– <i>dif</i> recombination complexes

Abstract

Significance Insight into the mechanisms that underlie the process of faithful chromosome segregation is of importance for understanding the place of humans in the living world. Bacteria are the most abundant free-living organisms and have important roles in human health and disease. Nevertheless, molecular understanding of bacterial chromosome segregation is in its infancy. In this paper, the action of one conserved molecular machine that acts to coordinate the late steps of chromosome segregation with cell division is analyzed molecule by molecule in real time, using three complementary single-molecule techniques simultaneously. By using normal and mutated proteins, the complete reaction pathway is revealed from assembly of the initial nucleoprotein complex, to its activation by a DNA motor, and to the subsequent steps that lead to chromosome unlinking.