Khalid Salaita

Nucleic acid probes that sense and respond to piconewton force enable new insights and applications in mechanobiology

Abstract: 

Cells are highly dynamic structures that are constantly converting chemical energy into mechanical work to pull and push on one another and on their surroundings. These pulls and pushes are mediated by tiny molecular forces at the scale of piconewtons. For context, 7 pN applied a distance of 1 nm is ~1 kcal/mol. Nonetheless, these forces can have profound biochemical consequences. For example, the rapidly fluctuating forces between immune cells and their targets can drastically tune immune response and function. Despite the importance of such forces, there are limited methods to study forces at the molecular scale and particularly at the junction of living cells. In this talk, I will discuss my group’s efforts at developing DNA mechanotechnology tools (1) to study the molecular dynamics of forces (2), the source of molecular forces at fluid membranes (3) and the development of new drug delivery strategies that employ forces (4). I will spend some time discussing force-triggered switches to detect molecular crowding at interfaces (5) and testing different models of mechanotransduction (6) in immunology.  I’ll end my talk describing the advent of new CRISPR catalytic amplification strategies for medical diagnostics which includes published (7) and unpublished work.

References:
1. Science, vol. 365, Issue 6458, pp. 1080-1081(2019)
2. J. Am. Chem. Soc. 2024, 146, 33, 23034–23043
3. Nature Nanotechnology https://doi.org/10.1038/s41565-024-01723-0 (2024)
4. Nature Communications volume 15, (2024) 
5. J. Am. Chem. Soc. 2024, 146, 10, 6830–6836
6. J. Am. Chem. Soc. 2024, 146, 11, 7233–7242
7. Nature Biomedical Engineering, volume 7, pages 1404–1418 (2023)

Speaker: Khalid Salaita, Emory University

Khalid Salaita is the Samuel Candler Dobbs Professor of Chemistry, and Director for Graduate Studies in the Chemistry Department at Emory University in Atlanta, Georgia (USA). Khalid grew up in Jordan and moved to the US to pursue his undergraduate studies at Old Dominion University in Norfolk, Virginia (USA). At that time he worked with Prof. Nancy Xu  studying the spectroscopic properties of plasmonic nanoparticles. He next pursued a PhD in Chemistry under the mentorship of Prof. Chad Mirkin at Northwestern University (Evanston, IL)  and graduated in 2006. During that time, he studied the electrochemical properties of organic adsorbates patterned onto gold films and developed massively parallel scanning probe lithography approaches. From 2006-2009, Khalid was a postdoctoral scholar with Prof. Jay T. Groves at UC Berkeley (USA) where he investigated the role of receptor clustering in modulating cell signaling. In 2009, Khalid started his own lab at Emory University, where he is currently investigating the use of nucleic acids as molecular force sensors, smart drugs, and synthetic motors. In recognition of his independent work, Khalid has received a number of awards, most notably: the Alfred P. Sloan Research Fellowship, the Camille-Dreyfus Teacher Scholar award, the National Science Foundation Early CAREER award, the Kavli Fellowship, and Merck Future Insight Prize. Khalid is currently the director of the Center on Probes for Molecular Mechanotechnology,  and an Associate Editor of SmartMat. Khalid’s program has been supported by NSF, NIH, and DARPA.

Host: Maria Mukhina

Seminars start at 4:00 pm, and refreshments will be served at 3:45 pm.

This seminar will be held in room 3150 of the Physical Sciences Complex (Bldg #415).