Identification and Protein Engineering of Galactosidases for the Conversion of Blood Type B to Blood Type O.
Moller, C., Terholsen, H., Schmoker, O., Le, T.L.A., Wesche, J., Schmiade, P., Eppendorfer, E., Rimkus, N., Girbardt, B., Bottcher, D., Palm, G.J., Hoppen, J., Lammers, M., Greinacher, A., Aurich, K., Bornscheuer, U.T.(2025) Chembiochem 26: e202500072-e202500072
- PubMed: 40013737 
- DOI: https://doi.org/10.1002/cbic.202500072
- Primary Citation of Related Structures:  
9I4F, 9I4G - PubMed Abstract: 
The supply of blood products such as red blood cells poses a challenge due to rising demand and declining donor numbers. Careful matching of blood products of different types is required. Only type O of the blood types A, B, AB and O can be received by any patient without transfusion incompatibilities. Therefore, O-type blood can be considered "universal blood" and is especially needed in emergency situations. In this study, we focused on the conversion of the B antigen by enzymatic deglycosylation to generate the H antigen determining O-type blood. For this, we characterized several previously unstudied α-1,3-galactosidases belonging to the GH110 family. Our findings revealed that the α-1,3-galactosidase from Pedobacter panaciterrae (PpaGal) exhibits superior efficiency compared to previously described galactosidases. We further increased the activity of PpaGal by 2.5-fold using site-directed mutagenesis. Moreover, we solved two crystal structures of PpaGal, one in the apo-state and another in complex with d-galactose. The combination of our mutagenesis study with the solved crystal structures provides valuable information to guide further optimization of PpaGal or other B antigen converting enzymes paving the way for the easier production of universal blood from B-type blood.
- University of Greifswald: Universitat Greifswald, Institute of Biochemistry, GERMANY.
Organizational Affiliation: