Carbohydrates and Glycoproteins

Flashcards covering key concepts and terminology related to carbohydrates and glycoproteins.

Monosaccharides

The simplest carbohydrates, which serve as monomers that make up polysaccharides.

Polysaccharides

Complex carbohydrates that are polymers of covalently linked monosaccharides.

Glycoproteins

Proteins that have carbohydrates covalently attached to them, constituting about 50% of the proteome.

O-glycosidic linkage

Covalent linkage formed between the anomeric carbon atom of a carbohydrate and the oxygen atom of an alcohol.

N-glycosidic linkage

Covalent linkage formed between the anomeric carbon atom of a sugar and the nitrogen atom of an amine.

Reducing sugar

A sugar that converts into a form with a free aldehyde group that is readily oxidized.

Glycation

The nonenzymatic addition of carbohydrates to proteins, usually occurring at lysine or arginine residues.

Lectins

Glycan-binding proteins that facilitate cell-cell contact and interactions.

Epimers

Diastereoisomers that differ at one of several asymmetric carbon atoms.

Anomers

Isomers that differ at a new asymmetric carbon atom formed on ring closure.

Chair and Boat conformations

The two classes of conformations that pyranose rings can adopt.

Glucosinolates

A class of glycosides produced by plants that serve as a defense against herbivory.

Proteoglycans

Proteins attached to glycosaminoglycans, functioning as structural components and lubricants.

A-D-Glucopyranose and B-D-Glucopyranose

Anomers of glucose that differ in the position of the hydroxyl group on the anomeric carbon.

A1C levels

The amount of glycated hemoglobin in the blood, used to assess diabetes management.

Sialic acid

A carbohydrate that influenza virus binds to for entry into host cells.

Secondary metabolites

Compounds produced by plants that may provide benefits against pathogens or herbivores.

Homopolymer

A polysaccharide made of the same monosaccharide units, such as glycogen or starch.

Chitin

A polysaccharide made of N-acetylglucosamine, found in the cell walls of fungi and exoskeletons of arthropods.

Cellulose

A structural polysaccharide of glucose with β-1,4 linkages, providing strength to plant cells.

Clinical biomarkers

Measurable signs of an illness, such as glycated hemoglobin for diabetes.