Directing Flux in Glycan Biosynthetic Pathways with a Small Molecule Switch

Abstract

Directing sugar traffic. Golgi‐resident glycosyltransferases act in concert to direct synthesis of a wide variety of cell‐surface glycans. A re‐engineered fucosyltransferase, whose activity is controlled with the small molecule rapamycin, can be used to divert flux away from production of one glycan (αGal) and toward synthesis of another (H antigen).

Glycoprotein Synthesis: An Update

“…Thus, rapamycin was used to regulate production of sLe x in living cells. In addition, CID has also been used to regulate α1,2-fucosyltransferase and therefore control competition between it and a 1,3-galactosyltransferase . Use of CID has also been applied to carbohydrate sulfotransferases …”

Enzymes in the Synthesis of Glycoconjugates

“…In this approach, the CTS and catalytic domains are expressed as separate fusion proteins that are each equipped with a unit of a chemically induced heterodimerization domain (CID, such as the rapimycin-dependent human rapamycin-associated protein (KFBP) and rapamycin-binding domain of mTOR (FRB) heterodimerizing domains) . In CHO cells, several CID schemes for controlled reconstitution of FucT and sulfotransferase activity have been demonstrated. − …”

Chemically Controlled Protein Assembly: Techniques and Applications

“…81,82 The Bertozzi lab demonstrated the use of the rapamycin CID system to investigate post-translational modification. 7,83,84 This intriguing strategy capitalized on two aspects of biosynthetic modularity and harnessed the CID mechanism with particular elegance. Controlled cellular localization of enzymes serves as an important functional regulator, demonstrated here by the requirement that glycosyl-and sulfotransferases must reside in the Golgi to function.…”