Brian Kelch, Associate Professor, Biochemistry & Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, will be giving a talk on "Peering under the hood of Nature's macromolecular machines: motors, rings, springs and things"

Zoom link: https://gc-cuny.zoom.us/j/91637964386

Meeting ID:  916 3796 4386. Passcode: asrc+ccny

ABSTRACT

       The Kelch Lab studies how large macromolecular machines function, focusing on the machinery underlying DNA replication and virus assembly. The replication machinery copies DNA with both high-speed and high-fidelity due to a circular sliding clamp to physically tether the DNA polymerase to the DNA. This ring-shaped sliding clamp requires a complicated ATPase machine called a Clamp Loader so that it can be correctly installed onto DNA. The Kelch lab studies the detailed mechanisms of clamp loading using a combination of structural biology, biochemistry and genetics. The clamp loader functions as a pentameric ATPase switch that uses a multi-step mechanism to place the sliding clamp onto DNA.
       The second part of my talk will focus on the machinery underlying virus function, which provides a fascinating example of self-assembly into a multi-partite molecular machine. Our studies of thermophilic viruses have revealed novel principles underlying virus stability and capacity. We also have revealed the mechanism of a molecular motor that is a pentameric ATPase similar to the clamp loader, but acts as a powerful and processive motor instead of a switch. I will discuss basic principles for ATPase function gleaned from our comparison of these two similar but distinct ATPase machines.