HEK293T-pST3Gal1LibFwd-MALII-2ndPos
Cells were sorted based on level of cell-surface enzyme activity using either lectins (MAL-II) or click-chemistry (with biotin tag). Enzymes expressed in individual enriched cell populations were sequenced using Illumina sequencers. The approach identified glycosyltransferase mutations that either enhanced or diminished wild-type enzyme activity.