nonglycosylated

Nonglycosylated refers to molecules that lack covalently attached carbohydrate moieties. In proteins and lipids, glycosylation is a common post-translational modification, including N-linked and O-linked glycosylation and GPI anchors. Nonglycosylated means that such carbohydrate attachments are absent.

In eukaryotes, most secreted and membrane proteins are glycosylated; nonglycosylated proteins are typically cytosolic, nuclear, mitochondrial, or derived from organisms that lack glycosylation pathways, such as many bacteria. Some proteins may remain nonglycosylated under specific mutations or experimental conditions.

Glycosylation affects folding, stability, trafficking, activity, and interactions, as well as immune recognition. Nonglycosylated variants can differ in stability or localization and may be more susceptible to proteolysis; however, they can function in contexts where glycosylation is unnecessary.

In research and biotechnology, nonglycosylated forms are often produced in bacterial expression systems and used as controls or starting points for structural studies. Therapeutic proteins may be engineered to be glycosylated or nonglycosylated to tailor pharmacokinetics and immunogenicity.

Related topics include glycosylation, glycoprotein, N-glycosylation, O-glycosylation, and deglycosylation.