Recombinant glycoproteins: The impact of cell lines and culture conditions on the generation of protein species

• Published in: Journal of proteomics 2016-02, Vol.134, p.85-92
• Main Authors: Rosenlöcher, Julia, Sandig, Grit, Kannicht, Christoph, Blanchard, Véronique, Reinke, Stefan O., Hinderlich, Stephan
• Format: Article
• Language: English
• Subjects: Glycoform; Glycoprotein species; Microheterogeneity; N-glycosylation; Protein species; Recombinant glycoprotein
• ISSN: 1874-3919
• DOI: 10.1016/j.jprot.2015.08.011

Glycosylation is the most complex post-translational modification. Thus, it contributes to versatile chemical compositions of proteins, leading to high amounts of protein species. The structural heterogeneity of glycoproteins was also described by the definition of glycoforms. We therefore introduced a new term called “glycoprotein species” to join the two concepts from different fields of biology. In this study, we further determined the theoretical numbers of glycoprotein species of two recombinant glycoproteins – a therapeutical antibody and the human protease inhibitor alpha-1-antitrypsin (A1AT) – based on structural analysis of their N-glycans. Moreover, we showed that variations in the used cell lines and their cultivation conditions strongly influence the number of glycoprotein species in case of recombinant A1AT production. Protein glycosylation is a major source for the huge amount of protein species. This study extends the sight of protein species by the following contributions: 1) The new term “glycoprotein species” was defined to introduce the concept of glycoforms into the field. 2) An estimation of the number of potential glycoprotein species of two particular glycoproteins was given. 3) The influence of production conditions for recombinant glycoproteins on glycoprotein species generation was displayed. [Display omitted] •The diversity of the proteome is increased remarkably by protein glycosylation.•N-glycans of two glycoproteins underwent structural analysis by mass spectrometry.•A calculation of potential glycoforms for both glycoproteins was presented.•The definitions of “glycoforms” and “protein species” were combined to a new term.