Lippincott Biochemistry Chapter 7 Carbohydrates

5 carbon sugar

ribose which is found in DNA & RNA

7 carbon sugar

SedoHeptulose which is important in pentose phosphate pathway

Sugar + aldehyde C||O|H

Aldoses

sugar + keto C||O ( acetone )

ketos

monosaccharides are linked by

glycosidic bonds

Oligosaccharides

3-10 monosaccharides

epimers

two sugars that differ only in the configuration around one carbon atom for example ,, glucose galactose mannose

glucose 4-carbon epimer is

galactose

glucose 2-carbon epimer is

mannose '' the place of the OH is different)

Glycongen is synthesized from

Alpha-D-Glucopyranose

cellulose is synthesized from

Beta-D-Glucopyranose

If the OH is on the LEFT...

L-Glucose (Beta) it

If the OH is on the right?

D-Glucose ,, (Alpha)

İn human body the glucose is always ?

D-Glucose ,, because the metabolism enzymes can bind to D-Glucose Only

furanose is a ____ membered ring while pyranose is found in

five membered ring ,, found in fructose ,, glucose

anomeric carbon

only carbon attached to two oxygens
-OH may point up or down

If the OH is up on the anomeric carbon it is labeled:

beta

if the OH is down on the anomeric carbon it is labeled

alpha

types of glycosidic bonds

N if attached to -Nh2 ,, O if attached to -OH

All sugar-sugar glycosidic bonds are

O-type linkages

the glycosylated protein in diabetes is

hemoglobin a1C

enzymes that break down glycosidic bond

glycosidases

Starch is composed of ________.

branched amylopectin and unbranched amylose

why are human not able to digest cellulose?

because we lack Beta-(1-4)endoglucosidases. thus we cant break the Beta(1-4) glycosidic bond of the cellulose

The high acidity of the stomach affect on alpha-amylase

it inactivates it

A (alpha)-amylase can't cleave

amylopectin &glycogen because they have alpha(1-6) bonds

Disaccharide are resistant to

lingual alpha amylase