transporter binding ABCB1 transporter substrate Substrate for the representitive member of the ABC transprorter family ABCB1 (MDR1, pgy1, P08183). ABC transporters preventing uptake or facilitating clearance of toxic substances, playing an important role in drug excretion through the bile. PSI-MI Algorithms have been published to predict the value of this parameter but the quality of the prediction is unknown. MI:2128 pgp(mdr1) substrate abcb1 substrate