Abstract :

Much of biological motion is driven by Molecular Motors. Motors are nanoscale machines that generate tiny force to walk along protein filaments inside the cell. As they walk, they carry different "cargoes". One example of a cargo is bacteria that are enclosed inside a "Phagosome" and transported to cellular locations where they can be killed in an acidic environment. We are now able to measure the number of motors transporting single phagosomes inside cells using an optical trap.

Our results suggest that a decisive switch in a phagosome's fate is because of the formation of cholesterol-rich domains called Lipid rafts on the phagosome. Motors geometrically cluster into these rafts, and by doing so are able to work cooperatively in large teams. I will discuss the biophysical evidence for this clustering, and the implications to infection by Mycobacterium Tuberculosis and Leishmania.

ABOUT THE SPEAKER:

Prof. Mallik is a biological physicist working at the Department of Biological Sciences, Tata Institute of Fundamental Research where he is an Associate Professor and Wellcome-DBT Senior Fellow. He completed an MSc in physics from the University of Allahbad before pursuing his doctoral studies in condensed matter physics at TIFR under the guidance of Prof. E.V. Sampathkumaran. During his postdoctoral work at TIFR, National Centre for Biological Sciences Bangalore and the University of California Irvine he began working on biological problems, including molecular motors. Prof. Mallik joined the faculty at TIFR in 2005. His work was recognised by the award of the Bhatnagar Prize for Biological Sciences in 2014.