title: Conformational shift in the closed state of GroEL induced by ATP-binding triggers a transition to the open state.
abstract: We investigated the effect of ATP binding to GroEL and elucidated a role of ATP in the conformational change of GroEL. GroEL is a tetradecamer chaperonin that helps protein folding by undergoing a conformational change from a closed state to an open state. This conformational change requires ATP, but does not require the hydrolysis of the ATP. The following three types of conformations are crystalized and the atomic coordinates are available; closed state without ATP, closed state with ATP and open state with ADP. We conducted simulations of the conformational change using Elastic Network Model from the closed state without ATP targeting at the open state, and from the closed state with ATP targeting at the open state. The simulations emphasizing the lowest normal mode showed that the one started with the closed state with ATP, rather than the one without ATP, reached a conformation closer to the open state. This difference was mainly caused by the changes in the positions of residues in the initial structure rather than the changes in "connectivity" of residues within the subunit. Our results suggest that ATP should behave as an insulator to induce conformation population shift in the closed state to the conformation that has a pathway leading to the open state.
authors.affiliation: Department of Biology, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan; Center for Informational Biology, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan; National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Yura
keywords: adenosine triphosphate; elastic network model; insulator; population shift; protein conformational change