Impact of nucleotide sugar metabolism on protein N-glycosylation in Chinese Hamster Ovary (CHO) cell culture

N-Glycosylation, a critical quality attribute that affects therapeutic protein efficacy, half-life and stability, occurs through a series of reactions where nucleotide sugars are sequentially attached to the asparagine residue of a protein. Nucleotide sugar abundance can impact glycan complexity and the final glycosylation profile. Recent advances in analytical technology have allowed for a faster, more efficient detection and quantification of nucleotide sugars. Stable isotope labeling has paved the way for identifying the intricate and interconnected pathways of nucleotide sugar biosynthesis. Additionally, nucleotide sugars and their precursors have been tested as media supplements to modulate glycosylation. A better understanding of nucleotide sugar profiles, coupled with glycosylation enzyme mechanisms, will help to elucidate what glycoengineering tools are needed to more effectively control and predict protein glycosylation.