J.R. Mesters, T. Hogg, E.B. KA¼ttner, M.S. Weiss, I. Kuta Smatanova and R. Hilgenfeld Institute of Biochemistry, University of LA¼beck, Ratzeburger Allee 160, ... The family of ABC-transporters are involved in the uptake of a wide range of molecules, protein export, and efflux of toxic substances. ... The proteins consist of two integral membrane domains and two cytoplasmic domains that hydrolyse ATP.