Sep 16 2008
Brandeis University has won a highly competitive $7.8 million grant from the National Science Foundation to establish a Materials Research Science and Engineering Center (MRSEC). The Center will study the effects of imposing constraints on materials, such as DNA confined in cells and the self-assembly of large arrays of rod-like virus particles, as a guide to engineering semiconductor nano-particles into shapes and forms suitable for applications such as biosensors and solar cells.
"Brandeis has been at the forefront of recent advances in materials science and biology, both in studying the properties of materials occurring in biological systems, and in understanding the role of material properties in the structure and function of cells and cellular components," said principal investigator Robert Meyer, a pioneer in the physics of liquid crystals.
The collaborative, interdisciplinary center will to try to produce a new category of materials known as "active matter." Distinct from normal inert materials such as plastics and steel, active matter can move on its own and exhibits properties previously only observed in living materials, such as muscle and cells.
"In general, we want to understand how biological gadgets are built out of materials, carefully structured and constrained, and from this to learn how to engineer functional bio-mimetic nano-systems for important applications," said Meyer.
The Brandeis center will involve physicists, biochemists, chemists, and biologists in a two-pronged approach to research. In a bottom-up approach, the researchers will explore how the addition of typical biological constraints, such as crowding and confinement, affects materials. For instance, DNA is a long polymer chain, confined to a small volume within a cell. How does this affect the dynamics of this molecule, for instance in division of an e.coli bacterium into two daughter cells? Likewise, the scientists want to understand how tethers added to the DNA in a cell nucleus affect how it can move to carry out important genetic processes.
In a top-down approach, the researchers will explore functioning cellular components, such as cilia, the organelles that miraculously move in synchronization to perform their jobs, such as keeping the lungs clear of pollutants. The researchers will essentially reverse engineer the function and structure of such "biological gadgets."
"Cilia are living machines that we're going to study by a combination of 3D electron microscopy, single particle experimentation, and genetic modification," explained Meyer. "We can genetically modify the structure of cilia, measure those changes with electron microscopy, and correlate them with the resulting changes of mechanical properties and function, as determined by physical experiments on a single cilium."
In constructing the first carefully controllable example of active matter, the center will study actin filaments, which propel themselves through space by getting longer at one end and shorter at the other in a process called tread-milling polymerization.
"How do these moving filaments feel the presence of their neighbors in a large organized array? How do they behave collectively? Are there rules? It's not really clear how these organized systems of self-propelled filaments will behave, but we get hints of some possibilities from observing flocks of birds and schools of fish," said Meyer. "Understanding the rules of behavior of this new kind of matter may help us understand processes like cell motility."
The goals of the new Center include benefits for both biology and materials science. The unique position of Brandeis, in combining just the expertise and technology needed in these two fields with an atmosphere of collaboration and an eagerness to explore uncharted fields, is what won the university this prestigious award, said Meyer.
"More than just a large grant, this puts Brandeis on the world map as one of the leaders in the exciting endeavor of combining physics and chemistry with the life sciences," Meyer said.