The ABO blood groups – comprising the A, B, AB and O blood types – are vitally important in blood transfusion and organ transplantation. The four types are differentiated by the presence or absence of two sugar antigens on the surface of red blood cells: a terminal alpha-1,3-linked N-acetylgalactosamine (A-antigen) or an alpha-1,3-linked galactose (B-antigen), both of which are absent in the O-blood type. As all individuals have antibodies to the antigen(s) they lack, transfusion with an incorrect blood type results in destruction of the incompatible blood cells, which can result in death. The enzyme EABase is capable of releasing both the A and B trisaccharides from the surface of red blood cells, giving it the potential to be used to convert blood cell types by the addition or removal of their antigens. Fathima Shaikh’s studies seek to determine the mechanisms underlying EABase activity, and identify the residues that are created as a result. Knowledge of these enzyme properties is crucial for the next stage of the project: engineering EABase into a glycosynthase, which is a mutant form of the enzyme that can synthesize (form) antigens, rather than removing them. She will conduct further work to optimize the efficiency of this glycosynthase, as well as increasing its synthetic utility by broadening its ability to transfer different sugars. If Shaikh’s experiments are successful, this process would allow for the conversion between blood groups. These enzymes could be of great benefit to human health, helping to overcome shortages in donated blood, and helping in the modification of related antigens on other cell types.