ATP-binding cassette transporter family member(s) (None)

ATP-binding cassette (ABC) transporters are a large and diverse superfamily of membrane proteins found in all domains of life. They are characterized by the presence of one or two highly conserved ATP-binding cassettes, also known as nucleotide-binding domains (NBDs), which harness the energy from ATP hydrolysis to drive the translocation of various substrates across cellular membranes. They play key roles in nutrient uptake/export; drug efflux; lipid/steroid/metabolite movement. Mutations can lead to inherited diseases and overexpression/dysfunction can lead to multidrug resistance.

Binding/hydrolysis of ATP at NBDs induces conformational changes in TMDs that alternately expose substrate binding sites to either side of the membrane—enabling unidirectional movement across lipid bilayers.