Seminar “Understanding DNA segregation during bacterial cell division with single-molecule super-resolution microscopy”

Date

Tuesday, 22nd February 20122

Time

12:00 am

Place

University of Barcelona
Faculty of Physics Building
Room 3.20, 3rd floor 

Speaker

Dr Marcelo Nollmann, Centre de Biochimie Structurale (France)

Abstract

ATP-fuelled molecular motors are responsible for rapid and specific transfer of double-stranded DNA during several fundamental processes, such as cell division, sporulation, bacterial conjugation, and viral DNA transfer. A dramatic example of intercompartmental DNA transfer occurs during sporulation in Bacillus subtilis, in which 3Mbp of chromosomal DNA are transported across a division septum by the SpoIIIE ATPase.

We previously showed that SpoIIIE translocates DNA at 5kbp/s while specifically interacting with highly skewed chromosomal sequences (SRS) that guide its directional motion. In addition, our data suggested that SpoIIIE assembles on a compartment-specific manner, though other reports proposed a different scenario.

Here, we use photoactivated localization microscopy, a recently developed super-resolution microscopy method, to directly visualize the architecture and the assembly dynamics of the SpoIIIE complex in live cells.