Manish Kumar and John Golbeck

Determining single molecule transport rates of light driven membrane proteins for optogenetic applications

Rhodopsins are unique membrane proteins that pump ions when exposed to light. While these proteins have been researched for decades a simple light driven transport does now exist. We are developing assays for measuring accurate per molecule transport rates for rhodopsins under various illumination conditions (see Figure). We are currently working on the chloride pump from Natromonas pharaonis isolated from highly saline lakes and the only sodium and lithium pump known – KR2 from the marine flavobacterium Krokinobacter eikastus. A surprising and totally science fiction type application of these pumps is in the field of optogenetics where parts of mammalian brains can be excited or “turned off”! In these applications these proteins are first expressed in neurons of mammals and then the neurons can either be hyperpolarized or silenced by creating or abolishing ionic gradients across membranes by the use of light.

The REU student will work with the Kumar group in Chemical Engineering and the Golbeck group in Biochemistry and Molecular Biology on the purification and characterization of rhodopsins and develop an independent project to integrate these proteins with block copolymers.

diagram explaining research project

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Contact Information

Manish Kumar, Ph.D.
Assistant Professor of Chemical Engineering
REU Program Coordinator

Esther Gomez, Ph.D.
Assistant Professor of Chemical Engineering
REU Program Coordinator



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