Date of Award
9-6-2024
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Chemistry
First Advisor
Miguel Ballicora
Abstract
The production of biofuels like ethanol has increased with the transition to renewable energy. Starch can be converted into ethanol through chemical modification. Increasing the availability of starch is crucial to fight back climate change thus, researchers have focused on the biotechnological modification of plants. This modification is known as transgenics, where a plant is modified by the insertion of genes, to make it as productive as possible. The genes inserted code for enzymes that control pathways responsible for the synthesis of certain biomolecules, in this case starch. The synthesis of starch in plants (as glycogen in both photosynthetic and heterotrophic bacteria) is controlled by the enzyme named ADP-glucose pyrophosphorylase (ADP-Glc PPase), which catalyzes the production of ADP-glucose (ADP-Glc) and pyrophosphate (PPi). This reaction is the first committed step in the biosynthetic pathway, making it an ideal target for protein engineering. Mutagenesis studies have shown areas in the enzyme that are crucial for its catalytic efficiency. Studying those areas will allow a better understanding of the relationship between structure and function. Further research must be gathered to fully understand and derive proteins capable of producing higher starch content in plants. In the dissertation presented, we tackled this problem by performing mutagenesis of specific residues hypothesized to be critical for catalysis. After mutagenesis, the proteins obtained are characterized through kinetic and binding analysis, as well as X-ray crystallography. Our research can directly contribute to the design and production of transgenic plants that can increase the amount of starch in plants.
Recommended Citation
Martinez-Ramirez, Gabriela, "Regulatory, Structural and Functional Studies of the ADP-glucose Pyrophosphorylase from Photosynthetic and Heterotrophic Organisms" (2024). Dissertations. 4136.
https://ecommons.luc.edu/luc_diss/4136
