The contributions of individual galactosyltransferases to protein specific N-glycan processing in Chinese Hamster Ovary cells.

•Study of individual galactosyltransferases involved in N-glycosylation in triple and quadruple CHO-K1 deletion cell lines.•Contributions of B4GALT2 and B4GALT3 are protein-dependent.•B4GALT1 alone is not sufficient for full galactosylation of EPO-Fc.•Link between impaired galactosylation and occurance of less processed glycan structures with terminal mannose.