The energy-coupling factor transporters are responsible for vitamin uptake in prokaryotes. Here, the X-ray crystal structure of the membrane-embedded, substrate-binding domain of a riboflavin transporter from Staphylococcus aureus is reported. The transporter adopts a previously unreported fold and contains a riboflavin molecule bound to a loop and the periplasmic portion of several transmembrane segments.
- Peng Zhang
- Jiawei Wang
- Yigong Shi