A helical lid converts a sulfotransferase to a dehydratase

Svetlana Pakhomova, Vanderbilt University
Mime Kobayashi, Weill Cornell Medicine
Jochen Buck, Weill Cornell Medicine
Marcia E. Newcomer, Vanderbilt University


We report here the crystal structure of retinol dehydratase, an enzyme that catalyzes the synthesis of anhydroretinol. The enzyme is a member of the sulfotransferase superfamily and its crystal structure reveals the insertion of a helical lid into a canonical sulfotransferase fold. Site-directed mutations demonstrate that this inserted lid is necessary for anhydroretinol production but not for sulfonation; thus, insertion of a helical lid can convert a sulfotransferase into a dehydratase.