- 2021-04-22 14:00 |
- Vivo en YouTube
Carlos Bustamante (University of California)
Many cellular processes are performed by highly specialized and evolved entities that function as molecular machines. Some of these protein machines operate cyclically converting chemical energy into mechanical work through the generation of force or torque and displacement. These machines are referred to as “molecular motors”. I will give examples of several molecular motors in the cell, as well as their classification in terms of their mode of operation. The mechanical paradigm in biology is not new; as I will show, these ideas have been around since the XVII century, but our understanding of their operation has increased enormously through the use of single molecule manipulation methods and of modern biophysical techniques such as optical tweezers. I will describe some of our recent results in the study of the DNA packaging motor of bacteriophage Phi29, including its impressive thermodynamic efficiency. This is a feature that is common to many motors of biological origin. I will then speculate about the possible origin of this energetic efficiency based on recent results about energy dissipation. I will end by describing the impressive coordination among the different parts of the packaging motor using high-spatial resolution optical tweezers.