CarbohydrateChemistryPart2:OtherCarbohydrates

Dr.KevinAhern

Nomenclature

Fischer Form Haworth Form

Disaccharides

• Sucrose(glucose+fructose)• Lactose(glucose+galactose)• Maltose(glucose+glucose)

Disaccharides• Comprised of two sugars

1

2

3 4

5

6

1

2

3

4

5

6

Sucrose

Glucose Fructose

α1, β2 Diglycosidic Links

α-D-glucopyranosyl-(1→2)-β-D-fructofuranoside

Sucrose

Fructose

1

2

34

5

6

Glucose 123

4

5

6

Disaccharides• Lactose and Maltose

Lactose Maltose

Glucose

Galactose

GlucoseGlucose

1

1

2

2

3

3

4

4

5

5

6

6

β-1,4 Glycosidic Bond

1 122

3 3

44

5 5

66

α-1,4 Glycosidic Bond

β-D-galactopyranosyl-(1→4)-D-glucose α-D-glucopyranosyl-(1→4)-D-glucose

ReducingVersusNon-ReducingSugars

Oligosaccharides

• Foundinglycoproteins• Playrolesincellularidentity

Polysaccharides

• Cellulose• Glycogen• Amylose• Amylopectin• Chitin

Glucose Glucose

Polysaccharides• Sugar Polymers With Glycosidic Bonds

Cellulose

β-1,4 Glycosidic Links

Polysaccharides• Sugar Polymers With Glycosidic Bonds

Glucose Glucose Glucose

Amylose - component of starch

α-1-4 Glycosidic Links

4 44 1 1 1

Amylose - component of starch

Polysaccharides

Amylopectin - component of starch

Glucose Glucose Glucose

GlucoseGlucose

α-1,4 Glycosidic Links

1 1 1444

α-1,6 Glycοsidic Link Branches

1 1

66

Polysaccharides

Polysaccharides• Sugar Polymers With Glycosidic Bonds

Glycogen

Glucose Glucose Glucose

GlucoseGlucose

α1,4 links

α1,6 links

ModifiedPolysaccharides

ChitinChitin in the wing of a sap beetle

ModifiedPolysaccharides

Pectin - gelling agent Galacturonic acid polymer α-1,4 bonds

PolysaccharidesBinding

Lectins - proteins that bind carbohydrates specifically Part of innate immune system Mannose binding lectin targets microbes

Phytohemagglutinins in plants Used by bacteria/viruses for cellular attachment Tamiflu inhibits neuraminidase necessary for exit of flu virus

Glycolipids• Glycoglycerolipids and Glycosphingolipids

Glycolipids• Glycoglycerolipids

Sugar

Diacylglycerol

Glycolipids• Glycosphingolipids

Cerebrosides

Single SugarSphingolipid Backbone

Glycolipids• Glycosphingolipids

Gangliosides

Sphingolipid Backbone

Complex Carbohydrate

Glycosaminoglycans-polyanionicpolymersofmodifiedsugarsProteoglycans-peptides/proteinslinkedtopolyanionicpolymersofmodifiedsugarsGlycoproteins-proteinslinkedtooligosaccharidesN-linked-joinedtoasparagineinprotein-E.R.andGolgiapparatusO-Linked-joinedtoserine/threonineinprotein-Golgiapparatus

Glycosylation

Glycosylation-glycoproteins

Glycosylation-Bloodtyping

Glycosaminoglycans• Unbranched polyanionic saccharide polymers

Chondroitin Sulfate

Heparin

MetabolicMelody

Structural Lullaby(To the tune of "Brahms' Lullaby")

Copyright © Kevin Ahern

In your sleepYou can keep

Learning more about sugarsFischer schemesHaworth rings

D & L and everything 

HydroxidesCan’t collide

Fav’ring chair over boat formSpatial guides

CoincideWith the way structures form