Biochemistry Carbohydrates

Ketose

What is a carbohydrate with a ketone functional group? ex. D-Fructose

Aldose

What is an carbohydrate with an aldehyde functional group? ex. D-Mannose, D-Galactose, and D-Glucose are all Aldohexose.

Aldose/Ketose

What are the two major classifications of monosaccharides?

Pyranose

Cyclic Monosacchrides with 6 member heterocyclic ring?

Furanose

Cyclic Monosacchride with 5 member ring

Beta anomer

OH group is ABOVE the plane of the ring

Alpha anomer

OH group is BELOW the plane of the ring

Glycosidic linkage

Anomeric -OH of one monosacchride can react with another -OH on another monosacchride forming a disacchride.

Maltose

Two alpha-D-Glucose molecules linked together by alpha 1-4 glycosidic link (derrived from starch)

Sucrose

Alpha-D-glucose linked to beta-D-fructose via 1,2 glycosidic linkage (puranose-furanose)

Lactose

Beta-D-galactose linked to alpha-D-glucose to give beta 1,4 glycoside

homopolysaccharide

made up of multiple units of same monosaccharide (starch, glycogen, cellulose, chitin)

heteropolysaccharides

Muliple units of more than one kind of monosaccharide (chondroitin sulfate, hyaluronic acid, heparin)

glycoconjugates

Carbohydrates that are covalently attached to a protein and lipid molecules (proteoglycans, glycoproteins, glycolipids)

Starch

Storage form of glucose found in plants, polymers of alpha-linked glucose; two types (amylose and amylopectin)

Amylose

Only 1,4 linkages; helical configuration, six glucose units per turn.

Amylopectin

Branched 1,4 and 1,6 linkages (1,6 is the branch) found in plants (starch).

Glycogen

Storage polysaccharide in animals, very highly branched.

Cellulose

Linear homopolymer of beta-D-glucose linked by beta-1,4 linkages (animals lack the enzymes neccessary to hydrolize).

Proteoglycans, glycoproteins, and glycolipids

Which is/are glycoconjugates?

Proteoglycans

Found in the extracellular matrix GAG chains which are linked to core proteins.

Glycoproteins

Examples include antibodies, human blood group antigens A, B, AB and hormones FSH, LH, TSH.

Glycolipids

Present in nerve tissue (brain) and cell membranes e.g. Gangliosides.

Alpha-Amylase

Secreted by salivary glands and pancrease; cleave alpha 1, 4 linkages; polysaccharides to monosaccharides

oligosaccharidases

Maltase (glu), sucrase (glu-fru), isomaltase (glu), lactase (glu-gal), and trehalase (glu) all represent what?

GLUT transporters

Absorption of monosaccharides can be can be done through __________. (via cotransport of monosaccharides with Sodium).

Hyaluronates

Which is a heteropolysaccharide composed of D-glucuronate and N-acetyl-D-glucosamine?

Chondroitin 4- and 6- sulfates

Which is a heteropolysaccharide composed of D-glucuronate and N-acetyl-D-galactosamine-4-sulfate?

Keratan sulfates

Which is a heteropolysaccharide composed of D-galactose and N-acetyl-D-glucosamine-6-sulfate?

Dematan sulfates

Which is a heteropolysaccharide composed of L-iduronate and N-acetyl-D-galactosamine-4-sulfate?

Heparin/Heparan sulfates

Which is a heteropolysaccharide composed of L-iduronate-2-sulfate and N-sulfo-D-glucosamine-6-sulfate?

Maltase

Which oligosaccharidase acts as an exoglucosidase cleaving only alpha-1,4 linkages to produce glucose?

Sucrase

Which oligosaccharidase hydrolyzes oligosaccharides to produce glucose and fructose?

Isomaltase

Which oligosaccharidase cleaves alpha-1,6 linkages to produce glucose?

Lactase

Which oligosaccharidase cleaves beta-glycosidase linkages to produce glucose and galactose?

Trehalase

Which oligosaccharidase cleaves trehalose to produce glucose?

Sucrase and Lactase

Which oligosaccharidase(s) produce either fructose or galactose in addition to glucose?

Maltase, Isomaltase, and Trehalase

Which oligosaccharidase(s) produce only glucose?

GLUT 5

Which GLUT transporter is important for transporting fructose?

GLUT 4

Which GLUT transporter is important for transporting into skeletal muscle, heart, and fat?

GLUT 3

Which GLUT transporter is important for transporting into neurons?

GLUT 2

Which GLUT transporter is important for transporting into Liver, islet beta-cells, kidney and small intestine?

GLUT 1

Which GLUT transporter is important for transporting into many tissues?