Speaker: German Rivas (Systems Biochemistry of Bacterial Division, CIB Madrid)
Subject: Reconstructing Minimal Divisomes in the test Tube
Location: Bionanoscience, TU Delft
Date: Tuesday, June 9 11:00-12:00
Author: Jasper Veerman
As bottom-up biology has become increasingly popular, scientists aim to construct the minimal cell. In trying to achieve this, a solid understanding of the splitting of a cell into two daughter cells is essential. In his research, German Rivas studies how elements of the so-called divisome are organized at the membrane.
Locating the site of division happens with tremendous precision, leaving scientists to wonder what robust mechanism underlies this process. FtsZ is an important molecule, that polymerizes around the membrane to form a ring-like structure. This structure is anchored to the cell membrane by ZipA, and can contract to split the cell contents.
Using pioneering techniques, like light scattering, ultracentrifugation and fluorescence correlation microscopy, Rivas studies the behavior of the above-mentioned molecules in lipid bilayers, vesicles and nanodisks. In ZipA containing vesicles, he was able to show that the polymerization of FtsZ resulted in cell shrinkage (division). Interestingly, this process could be controlled from outside the cell.
Some of the dynamics of the proto-ring assembly remind Rivas of his background in plaques, accumulation of molecules in a certain location. As a result, someday, Rivas wishes to unravel the effect of crowding on the assembly of the proto-ring, yielding insight in how cell-division processes can occur with such precision, despite all the busy cell contents moving about.