5IN5: Crystal Structure Of Gdp-mannose 4,6 Dehydratase In Complex With Natural Inhibitor Gdp-fucose

The efficacy of therapeutic antibodies that induce antibody-dependent cellular cytotoxicity can be improved by reduced fucosylation. Consequently, fucosylation is a critical product attribute of monoclonal antibodies produced as protein therapeutics. Small molecule fucosylation inhibitors have also shown promise as potential therapeutics in animal models of tumors, arthritis, and sickle cell disease. Potent small molecule metabolic inhibitors of cellular protein fucosylation, 6,6,6-trifluorofucose per-O-acetate and 6,6,6-trifluorofucose (fucostatin I), were identified that reduces the fucosylation of recombinantly expressed antibodies in cell culture in a concentration-dependent fashion enabling the controlled modulation of protein fucosylation levels. 6,6,6-Trifluorofucose binds at an allosteric site of GDP-mannose 4,6-dehydratase (GMD) as revealed for the first time by the X-ray cocrystal structure of a bound allosteric GMD inhibitor. 6,6,6-Trifluorofucose was found to be incorporated in place of fucose at low levels (<1%) in the glycans of recombinantly expressed antibodies. A fucose-1-phosphonate analog, fucostatin II, was designed that inhibits fucosylation with no incorporation into antibody glycans, allowing the production of afucosylated antibodies in which the incorporation of non-native sugar is completely absent-a key advantage in the production of therapeutic antibodies, especially biosimilar antibodies. Inhibitor structure-activity relationships, identification of cellular and inhibitor metabolites in inhibitor-treated cells, fucose competition studies, and the production of recombinant antibodies with varying levels of fucosylation are described.
PDB ID: 5IN5Download
MMDB ID: 142453
PDB Deposition Date: 2016/3/7
Updated in MMDB: 2016/11
Experimental Method:
x-ray diffraction
Resolution: 1.9  Å
Source Organism:
Similar Structures:
Biological Unit for 5IN5: tetrameric; determined by author and by software (PISA)
Molecular Components in 5IN5
Label Count Molecule
Proteins (4 molecules)
Gdp-mannose 4,6 Dehydratase(Gene symbol: GMDS)
Molecule annotation
Chemicals (13 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB