Vitamin uptake in prokaryotes is achieved by ECF (energy coupling factor) transporters. They are trans-membrane proteins of which their structure and transport mechanism is largely unknown however they transport substrates from one side of the membrane to the other. These ECF transporters contain a membrane-embedded substrate-binding protein known as the S-component. The S component is responsible for substrate binding and is specific to certain substrates.
In the case of Staphylococcus aureus, the ECF transporter we are particularly interested in is the ECF-type riboflavin transporter. The S component of this ECF transporter is known as RibU and it transports Riboflavin from the periplasm to the cytoplasm of the bacterium.
Staphylococcus aureus |
This study is a step towards understanding the mechanisms of ECF transporters. Presently there is little knowledge of S component interactions or ATP hydrolysis by the A components – more biochemical and structural studies are required.
Zhang, P, Wang, J and Shi, Y (2010) Structure and mechanism of the S component of a bacterial ECF transporter. Nature 468, 717–720. doi:10.1038/nature09488
