Biomolecules from a quantum viewpoint.

Biomolecules from a quantum viewpoint

Chemist have learned a great deal about the chemical dynamics of biological molecules by creating computer simulations of the molecules' structure and movement. These computer simulations use principles of classicaly physics, however, and some scientists worry that quantum mechanical effects may force a change in theories about how the molecules actually work.

A team of scientists from two universities has constructed the first quantum mechanical simulation of such a biomolecule and found important differences between the classical view of the molecule and the quantum mechanical view, they write in the Aug. 25 NATURE. J. Andrew McCammon and his colleagues at the University of Houston and Peter Wolynes at the University of Illinois in Urbana-Champaign simulated the molecular motions of atomic groups in the molecule ferrocytochrome C using quantum dynamic principles and found "significant differences" in how the stretching of chemical bonds and the oscillation of chemical groups was modeled.

Ferrocytochrome C is one of the molecules that pass electrons down an energy chain to make oxygen respiration possible. The differences in how the molecule appears when viewed through the lens of quantum mechanics will directly influence the expected rates of electron transfer in the process. The differences could change our view of how oxygen respiration evolved and have an impact on researchers who want to design new proteins with better electron transfer properties, McCammon says.

"This [simulation] could be used in research in biological, materials and energy sciences," McCammon says. "For instance, people think about using electron transfer proteins in solar energy devices and it might have some application there."