Computational Chemical Physics Group

Exploring Nature With Computer Simulations

April 19, 2017
by Danilo Roccatano

Citrate Synthase a Pac-Enzyme

Citrate Synthase (CS) is an enzyme localized in the mitochondria of our cells where it plays an important role in the aerobic respiration cycle by transforming oxaloacetate molecules (on the right side of the picture) in citrate (on the top left side) with the assistance of the acetyl-coenzyme A (CoA) molecule. As the pac-man in the famous computer game, this Pac-Enzyme diffuse along the space between the convolute cristae of mitochondria “chomping” at its encounter oxaloacetates that activate the enzyme to bind the CoA (ghosts in the playground). For each captured CoA, a new citrate molecule is then produced (score). This complex mechanism requires large conformation changes of parts of the protein (domains) whose molecular details are not yet clarified. Using molecular dynamics simulations on the ARCHER supercomputer, I am studying in collaboration with Dr. S. Hayward of the University of UEA (Norwich, UK)┬áthis enzyme to garner novel insights on structural, dynamics and thermodynamics of its functional mechanisms.
The following image was submitted to ARCHER Image Competition 2016
and it was selected for the September picture in the ARCHER calendar 2017.