Journal article

The maltose ABC transporter: Action of membrane lipids on the transporter stability, coupling and ATPase activity

Huan Bao, Kush Dalal, Victor Wang, Isabelle Rouiller, Franck Duong

Biochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism | ELSEVIER SCIENCE BV | Published : 2013

Abstract

The coupling between ATP hydrolysis and substrate transport remains a key question in the understanding of ABC-mediated transport. We show using the MalFGK2 complex reconstituted into nanodiscs, that membrane lipids participate directly to the coupling reaction by stabilizing the transporter in a low energy conformation. When surrounded by short acyl chain phospholipids, the transporter is unstable and hydrolyzes large amounts of ATP without inducing maltose. The presence of long acyl chain phospholipids stabilizes the conformational dynamics of the transporter, reduces its ATPase activity and restores dependence on maltose. Membrane lipids therefore play an essential allosteric function, th..

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