A method for engineering a bacterial strain to create eukaryotic glycoproteins is presented this week in Nature Chemical Biology. These results may have immediate importance for industrial production of glycoproteins that scientists use in looking for therapies for various diseases.

Presently, glycoproteins needed for medical treatments and scientific research are created using hard-to-manipulate eukaryotic cells to retain the specific glycans which are critical for biological function: Eukaryotic glycoproteins are labeled with a specific sugar-rich carbohydrate sequence that determines the localization, function, and stability of the corresponding protein. Bacteria also attach carbohydrates to some of their proteins, but the sugar structure is significantly different from the eukaryotic glycoproteins created.

Matthew DeLisa and colleagues now create an engineered E. coli cell that can produce a five-carbohydrate chain - the ‘core structure’ of the eukaryotic carbohydrate sequence - that can be further attached to several eukaryotic proteins made in the same cell.