Carbohydrates Flashcards
Amylopectin
a branched polymer, with an α-1,6-glycosidic bond for every 30 α-1, 4-glycosidic bonds.
Amylose
a linear polymer of glucose units linked by α-1,4-
glycosidic bonds.
Glycoproteins
The protein is the largest component by weight. Glycoproteins play
a variety of roles including as membrane proteins.
Proteoglycans
The protein is aYached to a par<cular type of polysaccharide called a glycosaminoglycan. By weight, proteoglycans are mainly carbohydrate. Proteoglycans play structural roles or act as lubricants
Mucins or mucoproteins
Like proteoglycans, mucins are predominantly carbohydrate. The protein is characteristically attached to the carbohydrate by N- acetylgalactosamine. Mucins are often lubricants.
In all classes of glycoproteins, carbohydrates are attached to the nitrogen atom in the side chain of ____
asparagine (N-linkage)
In all classes of glycoproteins, carbohydrates are attached to the oxygen atom of the side chain of ____
serine or threonine (O-linkage).
Glycosaminoglycans
are composed of repeating units of a disaccharide, one of which is a derivative of an amino sugar and one of which carries a negative charge, either as a carboxylate or sulfate.
Sucrose
a-1,B-2
Lactose
B-1,a-4
Maltose
a-1,a-4
glycogen
lined by α-1, 4-glycosidic bonds, with branches formed by α-1, 6-glycosidic bonds every 10 glucose units.
All N-linked polysaccharides consist of
a common pentasaccharide core, consisting of three mannoses, a six-carbon sugar, and two N-acetylgalactosamine units.
In blood group A
N-acetylgalactosamine is added to the O by a specific glycosyltransferase
In blood group B
galactose is added by another transferase
