Chemistry Program Presents
Minimal Cellular Systems:
From Catalysts in Compartments to
Life as We Know It
Tuesday, April 19, 2016
RKC 115
4:30 pm EDT/GMT-4
4:30 pm EDT/GMT-4
Dr. Aaron Engelhart
Harvard University
The emergence of homeostatic mechanisms that enabled maintenance of an intracellular steady-state during growth was critical to the advent of cellular life. Here, I will present our results showing that concentration-dependent reversible binding of short oligonucleotides, of both specific and random sequence, can modulate ribozyme activity. In both cases, catalysis is inhibited at high concentrations, and dilution activates the ribozyme via inhibitor dissociation, thus maintaining near-constant ribozyme specific activity throughout protocell growth.Harvard University
In a second portion of the talk, I will show our results demonstrating that model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg2+, which is required for ribozyme activity and RNA synthesis. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest that similar modified lipids could have played a key role in early life, and that primitive lipid membranes and encapsulated catalysts, such as ribozymes, may have acted in conjunction with each other, enabling otherwise-impossible chemical transformations within primordial cells.
For more information, call 845-752-2354, or e-mail [email protected].
Time: 4:30 pm EDT/GMT-4
Location: RKC 115