. "\"Catalysis of the transfer of a specific substance or related group of substances from one side of a membrane to the other, up the solute's concentration gradient. The transporter binds the solute and undergoes a series of conformational changes. Transport works equally well in either direction.\" [GOC:mtg_transport, ISBN:0815340729]" . . "active transmembrane transporter activity" . "carrier activity" . "permease activity" . "active carrier activity" . "pump activity" . .