Download Ch.05The Structure and Function of Large Biological Molecules

HO
1
2
3
H
Short polymer
HO
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
HO
1
H
2
3
H 2O
4
H
Longer polymer
(a) Dehydration reaction in the synthesis of a polymer
HO
1
2
3
4
Hydrolysis adds a water
molecule, breaking a bond
HO
1
2
3
H
H
H 2O
HO
H
(b) Hydrolysis of a polymer
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Aldoses
Trioses (C3H6O3)
Pentoses (C5H10O5)
Hexoses (C6H12O6)
Glyceraldehyde
Ribose
Ketoses
Glucose
Galactose
Dihydroxyacetone
Ribulose
Fructose
2
(a) Linear and ring forms
(b) Abbreviated ring structure
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1–4
glycosidic
linkage
Glucose
Glucose
Maltose
(a) Dehydration reaction in the synthesis of maltose
1–2
glycosidic
linkage
Glucose
Fructose
Sucrose
(b) Dehydration reaction in the synthesis of sucrose
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Chloroplast
Mitochondria Glycogen granules
Starch
0.5 µm
1 µm
Glycogen
Amylose
Amylopectin
(a) Starch: a plant polysaccharide
(b) Glycogen: an animal polysaccharide
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(a) α and β glucose
ring structures
α Glucose
(b) Starch: 1–4 linkage of α glucose monomers
β Glucose
(b) Cellulose: 1–4 linkage of β glucose monomers
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Cell walls
Cellulose
microfibrils
in a plant
cell wall
Microfibril
10 µm
0.5 µm
Cellulose
molecules
β  Glucose
monomer
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8
(a) The structure
of the chitin
monomer.
(b) Chitin forms the
exoskeleton of
arthropods.
(c) Chitin is used to make
a strong and flexible
surgical thread.
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Fatty acid
(palmitic acid)
Glycerol
(a) Dehydration reaction in the synthesis of a fat
Ester linkage
(b) Fat molecule (triacylglycerol)
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Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid
(a) Saturated fat
Structural formula
of an unsaturated
fat molecule
Oleic acid, an
unsaturated
fatty acid
cis double
bond causes
(b) Unsaturated fat
bending
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Hydrophilic head
Hydrophobic tails
(a) Structural formula
Choline
Phosphate
Glycerol
Fatty acids
Hydrophilic
head
Hydrophobic
tails
(b) Space-filling model
(c) Phospholipid symbol
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Hydrophilic
head
Hydrophobic
tail
WATER
WATER
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14
15
Substrate
(sucrose)
Glucose
OH
Fructose
Enzyme
(sucrase)
H2O
H
O
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α carbon
Amino
group
Carboxyl
group
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Nonpolar
Glycine
(Gly or G)
Valine
(Val or V)
Alanine
(Ala or A)
Methionine
(Met or M)
Leucine
(Leu or L)
Trypotphan
(Trp or W)
Phenylalanine
(Phe or F)
Isoleucine
(Ile or I)
Proline
(Pro or P)
Polar
Serine
(Ser or S)
Threonine
(Thr or T)
Cysteine
(Cys or C)
Tyrosine
(Tyr or Y)
Asparagine Glutamine
(Asn or N) (Gln or Q)
Electrically
charged
Acidic
Aspartic acid Glutamic acid
(Glu or E)
(Asp or D)
Basic
Lysine
(Lys or K)
Arginine
(Arg or R)
Histidine
(His or H)
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Peptide
bond
(a)
Side chains
Peptide
bond
Backbone
(b)
Amino end
(N-terminus)
Carboxyl end
(C-terminus)
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Groove
Groove
(a)
A ribbon model of lysozyme
(b)
A space-filling model of lysozyme
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Antibody protein
Protein from flu virus
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Primary
Structure
Secondary
Structure
Tertiary
Structure
Quaternary
Structure
β pleated sheet
+H
3N
Amino end
Examples of
amino acid
subunits
α helix
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Hydrophobic
interactions and
van der Waals
interactions
Polypeptide
backbone
Hydrogen
bond
Disulfide bridge
Ionic bond
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Polypeptide
chain
β Chains
Iron
Heme
α Chains
Hemoglobin
Collagen
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Normal hemoglobin
Primary
structure
1
2
3
4
5
6
7
Secondary
and tertiary
structures
β subunit
Normal
hemoglobin
(top view)
Val
His
Leu
Thr
Pro
Val
Glu
1
2
3
4
5
6
7
Exposed
hydrophobic
region
β subunit
α
Quaternary
structure
β
Function
Secondary
and tertiary
structures
Sickle-cell hemoglobin
β
α
Quaternary
structure
Primary
structure
Val
His
Leu
Thr
Pro
Glu
Glu
β
Sickle-cell
hemoglobin
β
α
Function
Molecules do
not associate
with one
another; each
carries oxygen.
Molecules
interact with
one another and
crystallize into
a fiber; capacity
to carry oxygen
is greatly reduced.
10 µm
Red blood
cell shape
Normal red blood
cells are full of
individual
hemoglobin
moledules, each
carrying oxygen.
α
10 µm
Red blood
cell shape
Fibers of abnormal
hemoglobin deform
red blood cell into
sickle shape.
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Denaturation
Normal protein
Renaturation
Denatured protein
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Polypeptide
Correctly
folded
protein
Cap
Hollow
cylinder
Chaperonin
(fully assembled)
Steps of Chaperonin 2
The cap attaches, causing the 3
Action:
cylinder to change shape in
such a way that it creates a
1
An unfolded polyhydrophilic environment for
peptide enters the
cylinder from one end.
the folding of the polypeptide.
The cap comes
off, and the properly
folded protein is
released.
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DNA
1
Synthesis of
mRNA in the
nucleus
mRNA
NUCLEUS
CYTOPLASM
mRNA
2
Movement of
mRNA into cytoplasm
via nuclear pore
Ribosome
3
Synthesis
of protein
Polypeptide
Amino
acids
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5ʹ′ end
Nitrogenous bases
Pyrimidines
5ʹ′C
3ʹ′C
Nucleoside
Nitrogenous
base
Cytosine (C)
Thymine (T, in DNA)
Uracil (U, in RNA)
Purines
Phosphate
group
5ʹ′C
(b) Nucleotide
3ʹ′C
Sugar
(pentose)
Adenine (A)
Guanine (G)
Sugars
3ʹ′ end
(a) Polynucleotide, or nucleic acid
Deoxyribose (in DNA)
Ribose (in RNA)
(c) Nucleoside components: sugars
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5' end
3' end
Sugar-phosphate
backbones
Base pair (joined by
hydrogen bonding)
Old strands
Nucleotide
about to be
added to a
new strand
3' end
5' end
New
strands
5' end
3' end
5' end
3' end
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