Pantothenate transporter FEN2 and similar transporters of the Major Facilitator Superfamily
This family is composed of Saccharomyces cerevisiae pantothenate transporter FEN2 (or fenpropimorph resistance protein 2) and similar proteins from fungi and bacteria including fungal vitamin H transporter, allantoate permease, and high-affinity nicotinic acid transporter, as well as Pseudomonas putida phthalate transporter and nicotinate degradation protein T (nicT). These proteins are involved in the uptake into the cell of specific substrates such as pathothenate, biotin, allantoate, and nicotinic acid, among others. The FEN2-like family belongs to the Major Facilitator Superfamily (MFS) of membrane transport proteins, which 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
Jiyao W et al.(2023). "The conserved domain database in 2023.",