Escherichia coli YfcJ, YhhS, and similar transporters of the Major Facilitator Superfamily
This subfamily is composed of Escherichia coli membrane proteins, YfcJ and YhhS, Bacillus subtilis uncharacterized MFS-type transporter YwoG, and similar proteins. YfcJ and YhhS are putative arabinose efflux transporters. YhhS has been implicated glyphosate resistance. YfcJ-like arabinose efflux transporters belong to the bacterial MdtG-like and eukaryotic solute carrier 18 (SLC18) family of the Major Facilitator Superfamily (MFS) of transporters. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.
Feature 1:putative chemical substrate binding pocket [chemical binding site]
Evidence:
Comment:based on the structures of MFS transporters with bound substrates, substrate analogs, and/or inhibitors
Comment:since MFS proteins facilitate the transport of many different substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides, the residues involved in substrate binding may not be strictly conserved among superfamily members
Comment:the substrate binding site or translocation pore has access to both sides of the membrane in an alternating fashion through a conformational change of the MFS transporter