guts session on carbohydrates and glycolipids dr. arrel toews (say tavz, like “waves”) 420 me...
TRANSCRIPT
![Page 1: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/1.jpg)
GUTS session on carbohydrates and glycolipids
Dr. Arrel Toews (say Tavz, like “waves”)
420 ME Jones Building
843-8727
A primer on carbohydrate and glycolipid structure, nomenclature, properties, and general functions
See also the GUTS carbohydrate/glycolipid notes (.doc) - self-assessment exam - additional information
![Page 2: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/2.jpg)
OXIDATION STATES OF CARBON: You better know!!
oxidation
OXIDATION: - loss of e-
- loss of H - gain of O
reduction
REDUCTION: (just the opposite) - gain of e-
- gain of H - loss of O
saturated alcohol aldehyde ketone carboxylic carbonhydrocarbon acid dioxide
H H O O Ol l ll ll ll
R-C-H R-C-OH R-C-H R-C-R R-C-OH O=C=Ol l H H
carbohydrates
fats
![Page 3: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/3.jpg)
SUGARS – CARBOHYDRATES - “hydrates of carbon”
Sugars - polyalcohols (-OH) + aldehyde = aldoseor + ketone = ketose
Simple sugars – monosaccharides2 sugars – disaccharidessugar polymers - polysaccharides
Need for: - energy fuel - energy storage - cell membranes/walls - cell-cell interactions
General formula: (CH2O)n
H—
H2
ClClC
—OH
—OH
H Ol aldehydegroup
Glyceraldehyde(an aldose)
C —OH lClC
O
—OH
H2
H2
ketonegroup
Dihydroxyacetone(a ketose)
H—
H2
ClClC
—OH
—OH
H Ol aldehydegroup
H—
H2
lClC
—OH
—OH
aldehydegroup
ald
C —OH lClC
O
—OHH2
H2
ketonegroup
C —OH lClC
O
—OHH2
H2
ketonegroup
)
![Page 4: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/4.jpg)
Fischer projection
OH
H-C l H-C-OH lHO-C-H l H-C-OH l C l CH2OH
O
1
6
5
4
3
2
C1
Open-chainstructure
O
H-C l H-C-OH lHO-C-H l H-C-OH l H- C-OH l CH2OH
1
6
5
4
3
2
Various ways to visualize the structure of glucose
H
OHH
OH
H
HO
HOCH2
HOH
H
O
1
6
5
4
3 2
Ring structure(Haworth projection)
Shorthand method of drawing sugar structures
(l = OH; C & H understood)
OOCH2OH
Space-filling model
![Page 5: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/5.jpg)
Constantly opening/closing but prefers ring
=
=
C1-OH
Glucose(open-chain form)
- OH on C5 links to C1 (aldehyde C)
- C1 changes from aldehyde to alcohol
- 6-sided (5-C, 1-O) ring forms
This is important for glycosidic links (hooking sugars together)
Glucose likes to form a ring in solution
-glucose
-glucose
O
H-C l H-C-OH lHO-C-H l H-C-OH l H- C-OH l CH2OH
1
6
5
4
3
2
H
OH
H
HO
HOCH2
HOH
H
6
5
4
3 2
OH HC O
1
OH
H
OH
H
H
HO
HOCH2
HOH
H
O
1
6
5
4
3 2
H
OHH
OH
H
HO
HOCH2
HOH
H
O
1
6
5
4
3 2
![Page 6: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/6.jpg)
fructose
- OH on C5 links to C2 (ketone C)
- C2 changes from ketone to alcohol
- 5-sided (4-C, 1-O) ring forms
Fructose likes to form a ring too!!
=
=
C2-OH
-fructose(ring form)
H2-C-OH l C O lHO-C-H l H-C-OH l H- C-OH l CH2OH
1
6
5
4
3
2
2
CH2OH lC
OH
HOCH2
OH
5OH
H
H
HO
Constantly opening/closing but prefers ring
HHO
HOCH2
OH
5
CH2OH
OH
2O
H
H
![Page 7: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/7.jpg)
sugar + ATP sugar~P + ADP
- Sugar~P are “primed for metabolism” – extra energy
- Key intermediates in: - energy production - biosynthesis
Phosphorylated sugars are “activated intermediates”
dihydroxyacetone-P glyceraldehyde-P glucose-6-P
kinase
O-
l-O-P O l O l CH2
H
OHH
OH
H
HO
HOH
H
O6
O-
l-O-P O l O l CH2
lH-C-OH l CH O
O-
l-O-P O l O l CH2
l C O l CH2OH
![Page 8: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/8.jpg)
N-glycosidic links (C-N bonds) are important too
Adenosine(the A in ATP)
Ribose
D-glucosamine(an amino-sugar)
H
OH
H
H
HO
HOCH2
HOH
H
O
NH3+
H
OH
HOCH2
H
O1
54
2
H
OHH
OH
H
H
HOCH2
H
O H
OHH
OH
D-ribose(ATP, RNA)
2-deoxyribose(DNA)
Important pentoses
3
2
H
OH
HOCH2
H
O
HH
OH
NH2
C NN C
HC CN N
CHAdenine
![Page 9: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/9.jpg)
Disaccharides – 2 sugars joined by glycosidic link
H
OHH
OH
H
HO
HOCH2
HOH
H
H
OHH
H
HO
HOCH2
HOH
1
6
5
4
3 2
C1
H
OHH
H
HO
HOCH2
HOH
H
1
6
5
4
3 2
-glucose glucose
OH
OO
HOH
hydrolysis
Hydrolysis (breaking a bond by addingwater across it) of glycosidic links regenerates sugar monomers
Formation of a glycosidic link locks C1 intospecific configuration (either or ).It CANNOT open or close anymore!!
This matters a lot,especially for di/polysaccharides
Maltoseglucose(-1,4)glucose
H
H
OH
H
HO
HOCH2
HOH
H
H
H
H
HOCH2
HOH
1
6
5
4
3 2
H
OHH
OH
H
HOCH2
HOH
H
1
6
5
4
3 2
H
H
H
HOCH2
HOH
14
3 2O
HOH
condensation
Glycosidic links between sugar monomersare formed by condensation (dehydration)reactions
O O
![Page 10: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/10.jpg)
Disaccharides – 2 sugars joined by glycosidic link
Sucrose(fruit sugar)
glucose + fructose
Cellobioseglucose(14)glucose
-glycosidic link (C1-OH is )
OH
HH
H
HO
HOCH2
HOH
H
O
1
OH
H
OH
H
H
HOCH2
HOH
H
O
14O
Lactose (milk sugar)galactose(14)glucose
-glycosidic link
H
OH
HOCH2
HOH
H
H
HOCH2
HOH
1
6
5
43 2
H
OHH
OH
H
HOCH2
HOH
H
1
6
5
3 2
H
H
H
HOCH2
HOH
14
3 2
OHO
HH
O O
![Page 11: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/11.jpg)
Important glucose polymers
AMYLOSE (starch in plants) long linear chains
(14 links in chains with 16 links at branches)
AMYLOPECTIN (starch in plants) & GLYCOGEN (animals) branched chains
1 4
1
6
1 4
(14 links)
1 4
(14 links)
CELLULOSE (in plants) long linear chains
1 4
![Page 12: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/12.jpg)
Glycosaminoglycans (GAGs)
aka mucopolysaccharides
long chains of disaccharide-repeat units - acidic sugar (- charge) - acetylated amino sugar (no charge)
Important components of: - extracellular matrix - synovial fluid of joints - mucus - vitreous humor of eye
Proteoglycans – proteins with lots of GAG chains attached
![Page 13: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/13.jpg)
Glucuronate N-acetyl- (acidic) glucosamine
Repeating disaccharides in hyaluronic acid
OCOO-
OH
OHO O
O
CH2OH
NH-C-CH3 ll O
HO
.............
An example of glycosaminoglycan (GAG) repeat unitsDon’t worry about the structures; just note the (-) charge
(repeat)(repeat)
Acetylation of NH2 group (otherwise present as NH3+)
prevents protonation, so no (+) charge present
![Page 14: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/14.jpg)
Other GAGs have even more (-) charges!
OCOO-
OH
OHO O
O
CH2OH
NH-C-CH3 ll O
HO
............. (repeat)(repeat)
Sulfate (SO4=) groups on various –OH (and to variable degrees)
in other GAGs. Sulfation makes them even more negative
SO4=
SO4=SO4
=
![Page 15: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/15.jpg)
GLY
CERO
LFATTY ACID
FATTY ACID
P
chol
ine
polar head long hydrophobic tail
GLY
CERO
LFATTY ACID
FATTY ACID
P
chol
ine
chol
ine
polar head long hydrophobic tail
Structures and properties are generally similar to phospholipids (amphipathic)
Phospholipids
Sphingolipids
F A T T Y A C I D
O
(usually)
Long-chain amino alcohol (sphingosine)sugar(s)
polar head long hydrophobic tail
Remember Sphingolipids??
(Glyco)
![Page 16: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/16.jpg)
base molecule is sphingosine (in black above)long-chain fatty acid (several different ones)
O
NH
CF A T T Y A C I D
X
O
OHA primer on sphingolipid nomenclature
(trans)S p h i n g o s i n e
if X = H, the molecule is ceramide (base of all sphingolipids)
if X = galactose, the molecule is cerebroside (galactosyl-ceramide, an important myelin lipid)if X = galactose-sulfate, the molecule is sulfatide (also a myelin component)if X = glucose, the molecule is glucosyl-ceramide
(precursor to gangliosides, globosides)
if X = P -choline, the molecule is sphingomyelin
![Page 17: GUTS session on carbohydrates and glycolipids Dr. Arrel Toews (say Tavz, like “waves”) 420 ME Jones Building atoews@med.unc.edu 843-8727 A primer on carbohydrate](https://reader035.vdocuments.us/reader035/viewer/2022062423/5697bf881a28abf838c89438/html5/thumbnails/17.jpg)
Vocabulary – do you know the meaning of the following terms?
oxidation vs reductionsugarsmono-, di-, and polysaccharidesglucosefructoselactosesucroseglycogenstarch (amylose and amylopectin)glycosaminoglycan (mucopolysaccharide)proteoglycansphingolipidsphingosineceramidesphingomyelincerebroside (and sulfatide)