60 by: Leone Johnson

Student – Leone Johnson

Enzyme – Pyruvate Dehydrogenase

EC # –  1.2.4.1

This enzyme is found in the mitochondrial matrix acting as a link between glycolysis and the TCA cycle.

Pyruvate dehydrogenase catalyses the process of adding pyruvate to lipoamide with the help of ThDP as a cofactor. ThDP helps pyruvate dehydrogenase by bonding to pyruvate while pyruvate dehydrogenase protonates the substrate and decarboxylases it as well. Pyruvate dehydrogenase catalyses an irreversible step when the two substrates are added to each other; It is then regulated from phosphorylation from PDK kinases. In addition to regulation from backflow of products that get in the way of the active site.

Mg attracts the phosphate groups in the Thiamine Diphosphate cofactor to hold it into place.

References:

Group, T. (no date) Mechanism and catalytic site Atlas , M-CSA Mechanism and Catalytic Site Atlas . Available at: https://www.ebi.ac.uk/thornton-srv/m-csa/entry/106/ (Accessed: 17 October 2024).

Patel, M.S. et al. (2014) The pyruvate dehydrogenase complexes: Structure-based function and regulation , The Journal of biological chemistry . Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC4059105/#:~:text=The%20pyruvate%20dehydrogenas e%20complex%20(PDC,of%20the%20tricarboxylic%20acid%20cycle. (Accessed: 17 October 2024).

Pyruvate dehydrogenase (no date) Pyruvate Dehydrogenase – an overview | ScienceDirect Topics . Available at: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/pyruvate-de hydrogenase (Accessed: 17 October 2024). (vii)