Please join Yale Chemistry for an Inorganic Chemistry Seminar with Marilyn Gunner, Professor of Biochemistry, Biology, Chemistry and Physics, from City College of New York.
Title: TBD
Biology stores energy in the transmembrane electrochemical gradient. Thus, moving electrons, protons, and ions through membrane-embedded proteins builds up a charge difference (∆V) and a difference in the concentration of protons (∆pH) and of other ions across the membrane. The Gunner Lab is especially interested in the function of the mitochondria and photosynthetic electron and proton transfer proteins. They are studying how the protein modifies the proton affinity and proton pathways through the reaction cycle of proton pumps.
A proton pump uses the energy of light (in photosynthesis) or metabolites (mitochondria and bacteria) to move protons from the high pH, negative, N-side of the membrane to the low pH, positive, P-side of the membrane. A basic proton pump has several minimal requirements including: (1) a change in proton affinity during the reaction cycle so protons will be bound from the N-side and released to the P-side via transiently loaded sites in the protein interior, a process that is thermodynamically uphill; (2) a pathway for protons to be handed from donor to acceptor through the hydrophobic interior of the membrane embedded region of the protein via a Grotthuss mechanism; (3) a means to close off proton transport so that the interior is only accessible to the N-side during proton uptake into the protein and accessible to the P-side during release to keep protons from moving downhill.
The Gunner Lab is currently studying Photosystem II, the type II bacterial photosynthetic reaction centers, Cytochrome c oxidase, NADH Q dehydrogenase, bacteriorhodopsin and the Cl/H antiporter. For more information about Prof. Gunner’s research: https://gunnerlab.ccny.cuny.edu/
Faculty Host: Prof. Gary Brudvig