Title:  The Nobel Prize in Physics, 2018 : Optical Tweezers and Nanoscale Biological Machines

Speaker :  Prof. Roop Mallik, Professor, Tata Institute of Fundamental Research (TIFR), Mumbai

Abstract: Arthur Ashkin was the first to move micron-sized particles using the radiation pressure of Lasers. His “Optical tweezer” is a microscopic version of the tweezer that you would use to place an electronic chip delicately on a printed circuit board. However, Ashkin never anticipated that his tweezer would one day measure tiny pico-Newton forces generated by the biological machines that power almost all life processes. Tweezers have revealed not just the force that such a Nanoscale molecular machine exerts, but also how the chemical and mechanical cycles within these machines are coupled to generate useful work.

We will discuss the physics behind optical tweezers, how to build one with minimal components, and the classic experiments that measure force from a single molecular machine in test-tube conditions. Such experiments, unfortunately, reveal little about how these machines are used in Nature. Recognizing this shortcoming, my Lab has developed methods to use optical tweezers inside living biological cells. The goal is to understand how large cooperative forces are generated by molecular machines during essential biological processes such as killing bacteria or distributing fat in the body. I will discuss the Mechano-biology that emerges from such measurements, and how it helps understand Biology in the language of Physics and Engineering.

About the speaker: Roop Mallik is a Professor at the Department of Biological Sciences at TIFR, and Senior Fellow of the Wellcome Trust-DBT India Alliance. Prof. Mallik has made fundamental contributions to the understanding of biological molecular motors. He has been awarded the Shanti Swarup Bhatnagar Award in Biological Sciences in 2014 by CSIR, Govt. of India. He is also a Fellow of the Indian Academy of Sciences, Bangalore.