sugars Flashcards Preview

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Flashcards in sugars Deck (57):
1

biologically active form of carbohydrates

D (dextrorotatory) - OH on right

2

aldotriose

glyceraldehyde

3

aldotetrose

erythrose

4

aldopentoses

xylose
arabinose
ribose

5

aldohexoses

galactose
mannose
glucose

6

ketotriose

dihydroxyacetone

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ketopentoses

xyulose
ribulose

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ketohexose

fructose

9

ketoheptulose

sedoheptulose

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enanitomers

nonsuperimposable mirror image that have at least one chiral center

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racemic mixture

equal amounts of 2 enanitomers; optically inactive

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diastereomers

stereoisomers that are not mirror images

13

epimers

diastereomers that different around one chiral center

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alpha configuration of haworth projection

OH down

15

beta configuration of haworth projection

OH up

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mutarotation

inter conversion between alpha and beta forms

17

dehydration synthesis

builds carbohydrates by the covalent interaction of glycosidic bonds between monosaccharides

18

sugar phosphate esters

addition of a phosphate group (PO3 2-) to a monosaccharide

19

aldonic acid

oxidation of aldehyde group of aldose sugars to produce carboxyl group

20

uronic acid

oxidation of 1 (primary) hydroxyl group of monosaccharide to carboxyl group

21

lactones

internal esterification of monosaccharide derivatives to form 5 and 6 member rings

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alditols

reduction of aldose or ketose carbonyl to hydroxyl group

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deoxy-sugars

one monosaccharide hydroxyl group is replaces with H atom

24

amino sugars

hydroxyl group of monosaccharide is replaces with amine group

25

sucrose

glucose + fructose
alpha-beta(1-2) glycosidic bond
NON reducing sugar

26

maltose

glucose + glucose
alpha(1-4) glycosidic bond
reducing sugar
hydrolysis of starch via diastases enzymes

27

lactose

galactose + glucose
beta(1-4) glycosidic bond
reducing sugar

28

cellobiose

glucose + glucose
beta(1-4) glycosidic bond
reducing sugar
partial hydrolysis of cellulose

29

glucan

polysaccharide made of ONLY glucose

30

starch

storage in plants
helical structures
2 main types: amylose and amylopectin

31

amylose

unbranched
alpha(1-4) glycosidic bond
one reducing end, one non-reducing

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amylopectin

same as amylose, except branched
branching = alpha(1-6) glycosidic bonds
branch every 24-30 residues

33

glycogen

storage in animals
branching every 8-12 residues
3D helical structure

34

where is glycogen stored? and what does it do?

skeletal muscle - fuel for muscle action
liver - regulates blood glucose levels

35

how is glycogen regulated?

by pancreatic hormones, insulin and glucagon

36

insulin

stimulates glucose uptake and glycogen formation

37

glucagon

stimulates glycogen breakdown

38

cellulose

major key for cell walls
beta(1-4) glycosidic bond
HUMANS CANNOT DIGEST

39

peptidoglycan

bacterial cell wall
beta(1-4) glycosidic bond
cross linked by peptides

40

lysozyme

breaks down peptidoglycan via hydrolyzing beat(1-4) bond

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where is lysozyme found?

tears, saliva, milk, and mucus

42

penicillin and other beta-lactams do what?

prevent peptide cross linkage in peptidoglycan

43

glycosaminoglycans (GAGs)

unbranched, repeating disaccharide
alternating uronic acid and reducing sugars
major key for ECM

44

examples of GAG's

hyraluronan
dermatologist
keratin sulfate
heparin

45

glucoconjugates

carbohydrate covalently bound to a protein or lipid; biologically active

46

proteoglycans

"core" protein with GAG chains attached via trisaccharide bridge to serine residue of protein

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where are proteoglycans found?

cell surface or ECM
important in cell differentiation and collagen formation

48

glycoproteins

proteins with one or more oligosaccharides joined covalently

49

o-linked

oligosaccharide attached to OH of serine or threonine
*golgi apparatus

50

n-linked

attached to amide N atom of asparagine
*RER

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glycosylation

process of adding carbohydrate groups

52

glycolipids

lipids with attached carbohydrate chain

53

where are glycolipids found? what are they bound to?

found mainly nerve cells
bound to cceramide

54

gangliosides

glycoshingolipid dervied from glucosylceramide containing 1 or more sialic acid

55

lipopolysaccharide

on gram negative bacteria
endotoxins to humans

56

sugar code

cells use specific oligosaccharide says carriers of secondary biological information

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lectins

proteins that read the sugar code