Steve Ealick's Research Group

Amycolatopsis orientalis BexX

PDB file:



The ability of BexX to selectively distinguish sulphur carrierproteins was given a structural basis in this work. This study was, to our knowledge, the first complete characterization of thiosugar formation in nature. It also demonstrates the receptor promiscuity of theA. orientalis sulphur-delivery system. BexX,has a protein sequence
and mode of action are similar to those of ThiG, which catalyzes thiazole formation in thiamine biosynthesis.

The BexX protomer is a classical (βα)8barrel.

Click the image to enlarge.

The active form of BexX is a dimer formed mostly by interactions between helices helices α7 and α8.

Click the image to enlarge.

The active site of BexX was identified by crystallization with reactant glucose-6-phosphate, which is converted to 2-thioglucose.

Click the image to enlarge.


Sasaki E, Zhang X, Sun HG, Lu MY, Liu TL, Ou A, Li JY, Chen YH, Ealick SE, and Liu HW. Co-opting sulphur-carrier proteins from primary metabolic pathways for 2-thiosugar biosynthesis. Nature 510:427-431 (2014). PubMed

Contacts Procedures Structures Projects Publications Lab Home Page Group Members