First domain of the pleiotropic drug resistance-like subfamily G of ATP-binding cassette transporters
The pleiotropic drug resistance (PDR) is a well-described phenomenon occurring in fungi and shares several similarities with processes in bacteria and higher eukaryotes. This PDR subfamily represents domain I of its (ABC-IM)2 organization. ABC transporters are a large family of proteins involved in the transport of a wide variety of different compounds including sugars, ions, peptides, and more complex organic molecules. The nucleotide-binding domain shows the highest similarity between all members of the family. ABC transporters are a subset of nucleotide hydrolases that contain a signature motif, Q-loop, and H-loop/switch region, in addition to, the Walker A motif/P-loop and Walker B motif commonly found in a number of ATP- and GTP-binding and hydrolyzing proteins.