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‫به نام خدا‬
Carbohydrates
Photosynthesis: Sun’s energy becomes
part of glucose molecule
energy
Carbon
dioxide
Water
Chlorophyll
‫گلوكز‬
,1%
of body weight
GLUCOSE
6 CO2 + 6 H20 + energy (sun)
C6H12O6 + 6 O2
‫‪Carbohydrates‬‬
‫‪-1‬کربوهیدراتها‬
‫‪ -2‬انواع کربوهیداتها‬
‫‪ - 3‬مونوساکاریدها (نامگذاری ‪ ،‬فرمول‪ ،‬ایزومر نوری‪،‬‬
‫‪D‬و‪L‬اپیمر ‪،‬انانتیومر‪،‬آنومر ‪)،‬‬
‫‪-4‬مشتقات مونوساکاریدها‪:‬‬
‫قندهای دزاکسی ‪ ،‬قندهای آمین دار‬
‫‪-3‬خواص مونوساکاریدها ‪:‬‬
‫گروه کربونیل(اکسیداسیون‪ ،‬اثربازها‬
‫‪،‬اسیدها ‪،‬مواداحیا کننده‪ ،‬هیروکسیل‬
‫آمین ‪،‬اسید سیانیدریک)‬
‫گروه هیدروکسیل(پیوند گلیکوزیدی ‪،‬‬
‫تشکیل استر)‬
‫‪ -5‬الیگو ساکاریدها ‪:‬‬
‫دی ساکاریدها (مالتوز‪ ،‬الکتوز‪،‬سلوبیلوز‪،‬‬
‫ساکاروز‪،‬تره هالوز)‬
‫‪ -6‬پلی ساکاریدها‪:‬‬
‫همو پلی ساکاریدها(نشاسته‪ ،‬گلیکوژن‪،‬دکستران‪،‬سلولز‪،‬کیتین)‬
‫هترو پلی ساکاریدها (اسید هیالورونیک ‪ ،‬هپارین‪ ،‬کراتان‪،‬درماتان‪ ،‬کنروئتین سولفات)‬
Carbohydrates (glucides, Osides…)
‫ساکاریدها‬،‫اوزیدها‬،‫گلوسیدها‬،‫کربوهیدارت ها‬
(CH2O)n
I
or H - C - OH
I
 Monosaccharides - simple sugars with multiple OH groups.
Based on number of carbons (3, 4, 5, 6), a monosaccharide
is a triose, tetrose, pentose or hexose. ‫مونوساكاريد‬
 Oligosaccharides - a few monosaccharides covalently
linked. (2-7) ‫اوليگوساكاريد‬
-Disaccharides - 2 monosaccharides covalently linked. ‫دي ساكاريد‬
-Trisaccharides - 3 monosaccharides covalently linked. ‫تری ساكاريد‬
 Polysaccharides - polymers consisting of chains of
monosaccharide or disaccharide units. ( 10…) ‫پلي ساكاريد‬
Monosaccharides
•
There are two families of monosaccharides:
1.
2.
Aldose- containing an aldehyde functional group
suffix –ose ‫ ( اوز‬Ribose) , Aldotriose…..
Ketose- containing a ketone functional group
(suffix -ul ‫ ( ُال‬Ribulose ) , Ketotriose…..
aldose
each have the same
formulae C3H6O3
ketose
‫ مدل فیشر‬-‫ساختمان خطی‬‫ساختمان قندها‬
‫ مدل هاوورث‬-‫ساختمان حلقوی‬-
‫ساختمان خطي مونوساكاريد ها‬
Linear Structure: Monosaccharides
Aldoses (e.g., glucose)
have an aldehyde group
at one end.
H
O
1C
H
HO
H
H
2C
3C
4
5
OH
Ketoses (e.g., fructose) have
a keto group, usually at C2.
:‫ایزومر عاملي‬
‫تفا وت در گروه عامل‬-
1
CH2OH
2
C
O
HO 3 C
H
H
C
OH
C
OH
6
CH2OH
D-glucose
H 4C
OH
H 5C
OH
6
CH2OH
D-fructose
‫‪D-ketoses‬‬
‫‪-3‬تریوزها‬
‫‪-4‬تتروزها‬
‫‪-5‬پنتوزها‬
‫‪-6‬هگزوزها‬
‫‪-7‬هپتوزها‬
‫‪D-aldoses‬‬
‫مونوساكاريد ها‬: ‫ايزومر‬
Monosaccharides :Isomers
Definition: Isomer
1-Functional isomers:. ‫ایزومر عاملي‬
2-Ring isomers: ‫ایزومر حلقه‬
3-Optical isomers: ‫ایزومر نوری‬
The number of isomers is 2n, where n is the number of asymmetric centers.
(R- aldose n=m-1 , R- ketose , L-aldose n=m-2, L-ketose n=m-3 , m=
number of carbon )
1- D &L Isomeri
2-(Enantiomers, Racemic ) ‫انانتيومر – راسميك‬
3-Epimerism Isomeri ‫ايزومر اپي مر‬
4-Anomerism Isomeri
‫ايزومر آنومري‬
‫ايزومر ‪ D ,L‬مونوساكاريدها‬
‫‪Monosaccharides : D ,L Isomers‬‬
‫قرار کرفتن گروه‪ OH‬بر روي آخرین كربن نامتقارن با هم تفاوت دارد‪.‬اگر در سمت راست باشد‬
‫قند از نوع ‪ D‬و اگر در سمت چپ باشد از نوع ‪ L‬است‪.‬قندهای مهم از لجاظ بیولوژیک‬
‫از نوع ‪ D‬هستند‪.‬برای نشان دادن جهت انحراف نور از عالمت ‪ +‬و‪ -‬استفاده می شود‪.‬‬
‫‪H‬‬
‫‪O‬‬
‫‪H‬‬
‫‪O‬‬
‫‪C‬‬
‫‪HO – C – H‬‬
‫‪H – C – OH‬‬
‫‪HO – C – H‬‬
‫‪HO – C – H‬‬
‫‪CH2OH‬‬
‫‪C‬‬
‫‪H – C – OH‬‬
‫‪HO – C – H‬‬
‫‪H – C – OH‬‬
‫‪H – C – OH‬‬
‫‪CH2OH‬‬
‫‪L-glucose‬‬
‫‪D-glucose‬‬
‫‪CHO‬‬
‫‪OH‬‬
‫‪C‬‬
‫‪CHO‬‬
‫‪H‬‬
‫‪CH2OH‬‬
‫‪H‬‬
‫‪C‬‬
‫‪HO‬‬
‫‪CH2OH‬‬
‫‪D-glyceraldehyde‬‬
‫‪L-glyceraldehyde‬‬
‫)‪Dextro (right‬‬
‫)‪Laevo (left‬‬
‫انانتيومرها‬
Monosaccharides :Enantiomers
• : A special subset of isomers when 2 sugars differ only
in the configuration around All carbon .
‫ بر روي تمام كربن هاي نامتقارن با هم تفاوت دارد‬OH,H ‫نحوه قرار گیري گروه‬
Enantiomers
‫اپي مرها‬
Monosaccharides: Epimers
: A special subset of isomers when 2 sugars differ only in
the configuration around one carbon.
‫ بر روي یكي از كربن هاي نامتقارن با هم تفاوت دارد‬OH,H ‫نحوه قرار گیري گروه‬
CHO
H
C
OH
HO
C
H
H
C
H
C
CHO
CHO
HO
HO
C
H
H
C
OH
C
H
HO
C
OH
H
C
OH
H
OH
H
C
OH
H
CH2OH
D-glucose
D-mannose
CH2OH
D-mannose
is a C-2
epimer of D-glucose!
CHO
H
C
OH
H
HO
C
H
C
OH
HO
C
H
C
OH
H
C
OH
CH2OH
D-glucose
CH2OH
D-galactose
D-galactose
is a C-4
epimer of D-glucose!
NOTE: D-mannose is NOT an epimer of D-galactose b/c
configuration about 2 carbons is different.
Ring Structures : ‫اثبات ساختمان حلقوي‬
• 1-Hemiacetal & hemiketal
• formation
‫اگر آلدئید با یك الكل واكنش دهد محصول آن نوعي استال است‬
‫در حالیكه واكنش مونوساكاریدها با الكل فقط همي استال است‬
R-OH
Hcl
H
OR
R
C
OR
‫استال‬
Acetal
2-Methylation ‫واكنش متیالسیون‬
glucose must be has 5 molecules methyl.
In practical it has 4 molecules .
Ring Structures
• Monosaccharides with 5 or more carbon atoms in the backbone
usually occur in solution as cyclic or ring structures.
‫فوران‬
O
furan
‫فورانوز‬

O
furanose
‫پیران‬
O
pyran
‫پیرانوز‬

O
pyranose
‫الفا دي گلوكوپیرانوز‬
‫بتا دي گلوكوپیرانوز‬
Ring Structures
When the ring forms, the –OH on the former carbonyl carbon can have two
configurations, given the designations  and .
In Haworth projection, the  - OH is down and the  -OH is up.
‫مدل هاوورث‬
These isomers
are called
anomers, and
the carbon atom
is referred to as
the anomeric
carbon atom.
‫ایزومر آنومري‬
‫كربن آنومریك‬
The interconversion between  and  forms occurs via the open-chain
structure in a reaction called mutarotation. ‫موتوروتاسیون‬
CH2OH
1
HO
H
H
2C
O
C
H
C
OH
C
OH
3
4
5
HOH2C 6
CH2OH
6
D-fructose (linear)
H
5
H
1 CH2OH
O
4
OH
HO
2
3
OH
H
-D-fructofuranose
Fructose forms either
 a 6-member pyranose ring, by reaction of the
C2 keto group with the OH on C6, or
 a 5-member furanose ring, by reaction of the
C2 keto group with the OH on C5.
Properties of carbonyl group
• Oxidation
1- aldehyde group
‫اسید گلوكونیك‬
‫اسید آلدونیك‬
2- Aldehyde & Alcoholic group
3- Alcoholic group
CHO
COOH
H
C
OH
HO
C
H
OH
H
C
OH
OH
H
C
OH
H
C
OH
HO
C
H
H
C
H
C
CH2OH
COOH
D-gluconic acid D-glucuronic acid
‫اسید گلوكورونیك‬
‫اسید اورونیك‬
)‫اسید گلوكاریك (ساکاریک‬
‫اسید الداریك‬
‫ اسید موسیک‬Gal
‫اثرات عوامل احيائ كننده‬
Effects of Reducing Agent:
The reducing agent can reduce keto group
and aldehyde group to hydroxyl group
‫مانیتول‬
D-Manose
Ribose
Galactose
‫سوربیتول‬
D-Glucose & fructose
Ribitol ‫ریبتول‬
Dolcitol ‫دولسیتول‬
‫واکنش با فنیل هیدرازین ‪:‬‬
‫تولید اوزازوان‬
‫شناسایی قند‬
‫‪-‬‬
‫کریستال‬
Effects of diluted
alkali :
Tautomerization
‫توتومریزاسیون‬
Mannose
Effects of Conc Acids:
Pentose
Furfural ‫فورفورال‬
Hexose
Hydroxy metyl Furfural ‫هیدروكسي متیل فورفورال‬
Effects of HCN : ‫اسید سیانیدریك‬
Production of a new sugar with a addition carbon
Effect of Hydroxyl Amine: ‫هیدروكسیل آمین‬
Production of a new sugar with lower a carbon
Reducing Sugars
• Monosaccharides are also known as
reducing sugars,
• Such reactions are used in the analysis of
sugars, e.g. Benedict’s Solution
RCHO + 2Cu2+

RCO2H + Cu2O
(RED)
‫معرف بندیكت‬
Properties of Hydroxyl Groups
• Hydroxy groups are modified in monosaccharides to give
a number of important derivatives:
Phosphorylation
‫فسفوریالسیون‬
Glycosides (elimination of water between anomeric
hydroxyl group and hydroxyl of another compound)
‫گلیكوزیدي‬
Glycosidic Bonds
The anomeric hydroxyl and a hydroxyl of another
sugar or some other compound can join together,
splitting out water to form a glycosidic bond:
‫پیوند‬
R-OH + HO-R'  R-O-R' + H2O
‫گلیكوزیدي‬
E.g., methanol reacts with the anomeric OH on glucose
to form methyl glucoside (methyl-glucopyranose).
H OH
H OH
H2O
H O
HO
HO
H
H
H
+
CH3-OH
H O
HO
HO
H
OH
H
OH
-D-glucopyranose
methanol
H
OH
OCH3
methyl--D-glucopyranose
Sugar derivatives
CH2OH
CH2OH
O
H
H
OH
H
H
OH
H
OH
OH
H
O
H
NH2
H
H
O OH
OH
H
N
C
CH3
H
-D-glucosamine
‫الفا دي گلوكز آمین‬
-D-N-acetylglucosamine
‫ان استیل گلوكز آمین‬
amino sugar - an amino group substitutes for a
hydroxyl on C-2. An example is glucosamine.
The amino group may be acetylated, as in
N-acetylglucosamine.
Sugar derivatives
H
O
H3C
C
O
NH
R
H
COO
H
R=
OH
H
HC
OH
HC
OH
CH2OH
OH
H
N-acetylneuraminate (sialic acid)
‫ان –استیل نورامنیك اسید –اسیدسیالیك‬
N-acetylneuraminate (N-acetylneuraminic acid, also called sialic
acid) is often found as a terminal residue of oligosaccharide
chains of glycoproteins.
Sialic acid imparts negative charge to glycoproteins, because its
carboxyl group tends to dissociate a proton at physiological pH,
as shown here.
Sugar derivatives
‫ریبوز‬
‫دزاكسي ریبوز‬
Structure of DNA ,RNA
NADH ,ATP,…...
‫ فوكوز‬L- Fucose = 6- Deoxy-L- Galactose
‫ رامنوز‬L-Ramnose =6-Deoxy -L- Manose
‫‪Oligosaccharides‬‬
‫‪ -2-7‬مونوساکارید با پیوندهای گلیکوزیدی به یکدیگر اتصال دارند‪.‬‬
‫•دی ساکارید ‪:‬‬
‫‪ -1‬احیائ کننده ‪ :‬مالتوز ‪ ،‬الکتوز‪ ،‬سلوبیلوز‬
‫‪ -2‬غیر احیائ کننده‪ :‬ساکاروز ‪،‬تره هالوز‬
‫•تری ساکارید‪ :‬مانند رافینوز(گلوکز‪-‬گاالکتوز‪-‬فروکتوز)‬
Disaccharides
•
Two Monosaccharides are covalently linked to one another by glycosidic
bonds that are acid labile, but base resistant. They are also hydrolyzed by
specific enzymes.
Writing the Structure of Disaccharides
1. the nonreducing end at the left.
2 The ring configuration is indicated by a suffix . ( osyl - ose) ‫اوز‬- ‫اوزيل‬
3. The atoms between which glycosidic bonds are formed are indicated
by numbers in parentheses between residue designations. ( 1
4)
CH2OH
O
CH2OH
O
+
OH
OH
HO
HO
OH
OH
6CH OH
2
5
O
CH2OH
H
O
H
OH
H
H
4
O
OH
OH
H
1
H
OH
3
H
OH
H
H
H
H
1
H
O
2
OH
‫مالتوز‬
OH
α -D-glucopyranosyl-(14)- α -D--glucopyranose.)
Disaccharides:
6 CH2OH
6 CH2OH
‫ مالتوز‬Maltose, a cleavage
H
5
O
5
H
H
O
H
H
H
1
product of starch, is a
1
4
4
H
H
OH
OH
disaccharide with (1 4)
O
OH
OH
2
2
3
3
glycosidic link between the
OH
H
OH
maltose H
C1 OH & C4 OH of 2
α -D-glucopyranosyl-(14)- α -D--glucopyranose
glucoses.
6 CH2OH
6 CH2OH
It is the  anomer (C1 O
5
5
O
O
OH
H
H
points down).
H
H
4
OH
OH
H
1
O
4
OH
H
3
H
2
OH
3
cellobiose
H
H
2
1
H
OH
β-D-glucopyranosyl-(14)- β -D--glucopyranose.)
‫ سلوبيوز‬Cellobiose, a product of cellulose breakdown, is the
otherwise equivalent  anomer .
The (1 4) glycosidic linkage is represented as a zig-zag,
but one glucose is actually flipped over relative to the other.
‫الكتوز‬Lactose, milk sugar, is composed of galactose & glucose, with β(14)
linkage from the anomeric OH galactose.
β -D-galactopyranosyl-(1 4)- β -D-glucopyranose
‫ ساكاروز‬Sucrose, common table sugar, has a glycosidic bond linking the anomeric
hydroxyls of glucose & fructose.
α -D-glucopyranosyl-(12)- β -D-fructofuranoside.
Disaccharides
Maltose
Glc(14)Glc
Cellobiose Glc(14)Glc
reducing maltase
Plants (starch)
Animals
(glycogen)
reducing cellulase
Plants (cellulose
dimer)
reducing Lactase
Milk (major
energy source)
Lactose
Gal (14)Glc
Sucrose
Sucrase
Fruits seeds
Glc(12)Fru nonreducing (invertase) roots and honey
Trehalose
Glu (11) Glc non-
reducing
Fungi
Polysaccharides
1-HomoPolysaccharides: ‫هوموپلي ساكاریدها‬
2-HeteroPolysaccharides: ‫هتروپلي ساكاریدها‬
•
The most important homopolysaccharides
involve D-glucose monomers and are:
1.
Glycogen- main storage polysaccharide of
animal cells
2. Starch (amylose and amylopectin)- main
storage polysaccharide of plant cells.
3. Cellulose- structural polysaccharide of plants
4. Chitin- major structural material in the
exoskeletons of many arthropods and mollusks.
(N-Acetyl Glucose Amine )n 1
4
5. Inolin ( D fructofuranose)n 1 2
Starch:‫نشاسته‬
There are two forms of starch
1-‫ آميلوز‬-amylose: D-glucose linked
(14) with no branching,20-15 %
,60-600 Glu,
2-‫آمیلوپكتین‬amylopectin: D-glucose
linked (14) and (16) with
branching,80-85% ,600.00,
24-30 Glc Branching site
-amylose
amylopectin
Glycogen:‫گليكوژن‬
•
•
•
.
Glycogen is comprised of D-glucose monomers linked
(14) and (16) Therefore,
it is a highly branched structure.
Glycogen is hydrolyzed by enzymes. located in animal cells.
Cellulose: ‫سلولز‬
• Cellulose is comprised
of D-glucose monomers
linked (14).
• 300-3000 unit.
• Cellulose is hydrolyzed by the enzyme cellulase.
• Vertebrates can not hydrolyze cellulose because
they lack the enzyme cellulase. Microorgnisms in
ruminants do produce cellulase and therefore
cattle, sheep, goats, etc utilize cellulose indirectly.
2-HeteroPolysaccharides
Glycoproteins and Proteoglycans
‫گلیكوپروتئین ها‬
Glycoproteins
‫پروتئو گالیكن ها‬
Proteoglycans
Proteins conjugated to
saccharides lacking a
serial repeat unit
Proteins conjugated to
polysaccharides with
serial repeat units
‫ گالیكوزوآمینوگالیكن ها‬Glycosaminoglycans
‫ موكوپلي ساكاریدها‬Mucopolysaccharides
Protein >> carbohydrate
Carbohydrate >> protein
Repeat unit
HexN and HexUA
Glycoproteins
•
Oligosaccharides are covalently attached to
proteins in one of two ways:
1.
2.
•
N-linked: CHO to Asn found within the protein
sequence Asn-X-Ser(Thr) where X is almost
any amino acid (except Pro, Asp or Glu). The
CHO is most often GlcNAc and sometimes
GalNAc. ‫آسپارژين‬
O-linked: CHO to Ser or Thr or hydroxylysine
or hydroxylproline. The CHO is most often
GalNAc. All blood group antigens are
oligosaccharides O-linked to both proteins and
lipids. ‫سرين –تره اونين‬
Oligosaccharides that are linked to proteins
are generally called carbohydrate moieties
Glycopeptide bonds
CH2 OH
O
O
H
HN
C
NH2
CH2
CH
Asn
H
Glc
H
OH
H
Type I
Protein
O H
OH
HN
C
CH3
NAc
N-Glycosyl linkage to Asn
CH2 OH
NH2
O
H
O
CH2
CH
H
Glc
OH
H
O H
OH
H
Type II
COOH
HN
C
CH3
NAc
O-Glycosyl linkage to Ser (Thr)
COOH
Ser
Protein
‫گليکو ليپيد ها‬
‫قند‪+‬چربي لیپید>قند ‪:‬مانند لیپو پلي ساکارید باکتریها‬
‫قند>لیپید‪:‬گلیکولیپیده (آنتي ژنهاي گروه خوني)‬
‫‪Blood group antigen‬‬
‫گروه خوني ‪O‬‬
‫گروه خوني ‪A‬‬
‫گروه خوني ‪B‬‬
‫موكوپلي ساكاريدها‬
Glycosaminoglycans
-1,3
COO
-
O
H
O
O H
H
O
H
OH
H
H
H
H
-1,4
CH2 OH
OH
H
GlcUA
HN
C
CH3
GlcNAc
‫اسید گلوكورونیك‬
‫اسید هیالورونیك‬
Hyaluronate
O H
OH
- ‫استیل گلوكز آمین‬-N-
No sulfate
-1,3 glycosidic linkage
Glycosaminoglycans
‫اسید یدورونیك‬
- ‫استیل گاالكتوز آمین‬-N-1,4
-1,3
H
CH2 OH
O
H
O
O OSO3
COO -
Dermatan sulfate ‫درماتان سولفات‬
O
H
H
OH
H
H
H
OH
IdUA
-1,4
O H
H
H
HN
C
CH3
GalNAc
-1,3
COO -
CH2 OH
O
H
H
OH
O
H
H
H
H
H
O
O OSO3
OH
O H
H
H
HN
C
CH3
GalNAc
GlcUA
‫ كند روتئین سولفات‬Chondroitin sulfate
‫اسیدگلوكورونیك‬
- ‫استیل گاالكتوز آمین‬-N-
Glycosaminoglycans
‫ گاالکتوز‬- ‫استیل گلوكز آمین‬-N-
-1,3
-1,4
CH2 OSO3 -
CH2 OH
O
OH
H
O
H
H
O
H
H
OH
H
H
H
OH
GlcUA
O
-1,4
O H
H
HN
C
-1,4
CH3
GlcNAc
COO -
CH2 OSO3 O
H
H
Keratan sulfate ‫كراتان سولفات‬
OH
O
H
H
H
OH
H
H
O
H
IdUA
OSO3 -
H
O
H
NHSO 3-
GlcAmine
‫ هپارین‬Heparin
‫ اسیدیدورونیك‬- ‫استیل گلوكز آمین‬-N
Hemiacetal & hemiketal
formation
H
An aldehyde can
react with an
alcohol to form a
hemiacetal.
C
O
+
R'
OH
R'
O
R
C
OH
R
aldehyde
alcohol
hemiacetal
R
C
A ketone can react
with an alcohol to
form a hemiketal.
H
R
O
+
"R
OH
R'
ketone
"R
O
C
R'
alcohol
hemiketal
OH
6 CH2OH
6 CH2OH
5
H
4
OH
H
OH
3
H
O
H
H
1
2
OH
-D-glucose
OH
5
H
4
OH
H
OH
3
H
O
OH
H
1
2
H
OH
-D-glucose
Cyclization of glucose produces a new asymmetric center at
C1. The 2 stereoisomers are called anomers,  & .
Haworth projections represent the cyclic sugars as having
essentially planar rings, with the OH at the anomeric C1:
  (OH below the ring)
  (OH above the ring).
H OH
4
H OH
6
H O
HO
HO
H O
HO
H
HO
5
3
H
H
2
H
OH 1
OH
-D-glucopyranose
H
OH
OH
H
-D-glucopyranose
Because of the tetrahedral nature of carbon bonds,
pyranose sugars actually assume a "chair" or "boat"
configuration, depending on the sugar.
The representation above reflects the chair configuration
of the glucopyranose ring more accurately than the
Haworth projection.
Sugar derivatives
CH2OH
H
C
OH
H
C
OH
H
C
OH
CH2OH
D-ribitol
 sugar alcohol - lacks an aldehyde or ketone; e.g., ribitol.
 sugar acid - the aldehyde at C1, or OH at C6, is oxidized
to a carboxylic acid; e.g., gluconic acid, glucuronic acid.
Polysaccharides
6CH OH
2
5
O
CH2OH
H
O
H
OH
H
H
1
H
O
OH
H
4 OH
OH
O
H
H
OH
H 1
O
H
H
H
OH
H
H
O
O
H
H
O
H
OH
H
H
O
OH
2
3
H
H
CH2OH
CH2OH
CH2OH
H
H
OH
H
OH
H
OH
OH
amylose
Plants store glucose as amylose or amylopectin, glucose
polymers collectively called starch. Glucose storage in
6CHosmotic
CH OH
CH OH
OH minimizes
OH
polymericCH
form
effects.
2
O
5
2
2
2
O
H
O
H
H
Amylose is a glucose
polymer with
(14) linkages.
It OH
H
H 1
H 1
O
O
O
adoptsOH
a helical conformation.
2
3
H
H
OH
H
OH
H
H
H
4 OH
H
OH
H
H
OH
H
OH
H
The end of the polysaccharide with an anomeric
amylose C1 not
involved in a glycosidic bond is called the reducing end.
H
CH2OH
CH2OH
O
H
H
OH
H
H
OH
H
O
OH
CH2OH
H
H
OH
H
H
OH
H
H
OH
CH2OH
O
H
OH
O
H
OH
H
H
O
O
H
OH
H
H
OH
H
O
amylopectin
H
1
O
6 CH2
H 5
H
4 OH
3
H
CH2OH
O
H 1
2
OH
H
H
O
CH2OH
O
H
4 OH
H
H
H
H
O
OH
O
H
OH
H
H
OH
H
OH
Amylopectin is a glucose polymer with mainly (14)
linkages, but it also has branches formed by (16) linkages.
Branches are generally longer than shown above.
The branches produce a compact structure & provide multiple
chain ends at which enzymatic cleavage can occur.
CH2OH
CH2OH
O
H
H
OH
H
H
OH
H
O
OH
CH2OH
H
H
OH
H
H
OH
H
H
OH
CH2OH
O
H
OH
O
H
OH
H
H
O
O
H
OH
H
H
OH
H
H
O
4
glycogen
H
1
O
6 CH2
5
H
OH
3
H
CH2OH
O
H
2
OH
H
H
1
O
CH2OH
O
H
4 OH
H
H
H
H
O
OH
O
H
OH
H
H
OH
H
OH
Glycogen, the glucose storage polymer in animals, is
similar in structure to amylopectin. But glycogen has
more (16) branches.
The highly branched structure permits rapid release of
glucose from glycogen stores, e.g., in muscle during
exercise. The ability to rapidly mobilize glucose is more
essential to animals than to plants.
CH2OH
H
O
H
OH
H
OH
H
1
O
H
H
OH
6CH OH
2
5
O
H
4 OH
3
H
H
H 1
2
OH
O
O
H
OH
CH2OH
CH2OH
CH2OH
H
H
O
O
H
OH
H
OH
O
H
O
H
OH
H
OH
OH
H
H
H
H
H
H
H
OH
cellulose
Cellulose, a major constituent of plant cell walls,
consists of long linear chains of glucose with
(14) linkages.
Every other glucose is flipped over, due to the 
linkages.
This promotes intra-chain and inter-chain Hbonds and
van der Waals interactions, that cause
cellulose chains to be straight & rigid,
and pack with a crystalline arrangement
in thick bundles called microfibrils.
Monosaccharides can form ring
structures
O
Furan
O
Pyran
Glycosidic binds are between two
sugars
They can either be in the  or  configuration and
can be linked through the 1-2, 1-4 or 1-6 linkage