Figure 1.

Overall Structure of YkoE

(A) Comparison of the architectures between group I and group II ECF transporters. Group II ECF modules can share several different S components, whereas group I S components are specific for their cognate ECF module, with all partners generally found in an operon together.

(B) Genetic organization of ykoEDC operon. The entire operon is under the regulation of the THI box, a thiamine-responsive riboswitch. The function of YkoF (green), an oligomeric, soluble thiamine-binding protein is currently unclear.

(C) Ribbon depiction of the overall conformation of YkoE.

(D) Cartoon representation of the orientation of individual helices in YkoE.