The Structure and Function of Large Biological Molecules презентация

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1. The Structure and Function of Large Biological Molecules
2. Overview: The Molecules of Life All living
3. Fig. 5-1
4. Concept 5.1: Macromolecules are polymers, built from
5. A condensation reaction or more specifically a
6. Fig. 5-2 Short polymer HO 1 2
7. Fig. 5-2a Dehydration removes a water molecule,
8. Fig. 5-2b Hydrolysis adds a water molecule,
9. The Diversity of Polymers Each cell has
10. Concept 5.2: Carbohydrates serve as fuel and
11. Sugars Monosaccharides have molecular formulas that are
12. Fig. 5-3 Dihydroxyacetone Ribulose Ketoses Aldoses Fructose
13. Fig. 5-3a Aldoses Glyceraldehyde Ribose Glucose Galactose Hexoses (C6H12O6) Pentoses (C5H10O5) Trioses (C3H6O3)
14. Fig. 5-3b Ketoses Dihydroxyacetone Ribulose Fructose Hexoses (C6H12O6) Pentoses (C5H10O5) Trioses (C3H6O3)
15. Though often drawn as linear skeletons, in
16. Fig. 5-4 (a) Linear and ring forms (b) Abbreviated ring structure
17. Fig. 5-4a (a) Linear and ring forms
18. Fig. 5-4b (b) Abbreviated ring structure
19. A disaccharide is formed when a dehydration
20. Fig. 5-5 (b) Dehydration reaction in the
21. Polysaccharides Polysaccharides, the polymers of sugars, have
22. Storage Polysaccharides Starch, a storage polysaccharide of
23. Fig. 5-6 (b) Glycogen: an animal polysaccharide
24. Glycogen is a storage polysaccharide in animals
25. Structural Polysaccharides The polysaccharide cellulose is a
26. Fig. 5-7 (a)  and  glucose
27. Fig. 5-7a (a)  and  glucose ring structures  Glucose  Glucose
28. Fig. 5-7bc (b) Starch: 1–4 linkage of
29. Polymers with α glucose are helical Polymers
30. Fig. 5-8 Glucose monomer Cellulose molecules
31. Enzymes that digest starch by hydrolyzing α
32. Fig. 5-9
33. Chitin, another structural polysaccharide, is found in
34. Fig. 5-10 The structure of the chitin
35. Concept 5.3: Lipids are a diverse group
36. Fats Fats are constructed from two types
37. Fig. 5-11 Fatty acid (palmitic acid) Glycerol
38. Fig. 5-11a Fatty acid (palmitic acid) (a)
39. Fig. 5-11b (b) Fat molecule (triacylglycerol) Ester linkage
40. Fats separate from water because water molecules
41. Fatty acids vary in length (number of
42. Fig. 5-12 Structural formula of a saturated
43. Fig. 5-12a (a) Saturated fat Structural
44. Fig. 5-12b (b) Unsaturated fat Structural
45. Fats made from saturated fatty acids are
46. A diet rich in saturated fats may
47. The major function of fats is energy
48. Phospholipids In a phospholipid, two fatty acids
49. Fig. 5-13 (b) Space-filling model (a)
50. Fig. 5-13ab (b) Space-filling model (a)
51. When phospholipids are added to water, they
52. Fig. 5-14 Hydrophilic head Hydrophobic tail WATER WATER
53. Steroids Steroids are lipids characterized by a
54. Fig. 5-15
55. Concept 5.4: Proteins have many structures, resulting
56. Table 5-1
57. Animation: Structural Proteins Animation: Storage Proteins Animation:
58. Enzymes are a type of protein that
59. Fig. 5-16 Enzyme (sucrase) Substrate (sucrose) Fructose Glucose OH H O H2O
60. Polypeptides Polypeptides are polymers built from the
61. Amino Acid Monomers Amino acids are organic
62. Fig. 5-UN1 Amino group Carboxyl group  carbon
63. Fig. 5-17 Nonpolar Glycine (Gly or G)
64. Fig. 5-17a Nonpolar Glycine (Gly or
65. Fig. 5-17b Polar Asparagine (Asn or
66. Fig. 5-17c Acidic Arginine (Arg or
67. Amino Acid Polymers Amino acids are linked
68. Peptide bond Fig. 5-18 Amino end (N-terminus)
69. Protein Structure and Function A functional protein
70. Fig. 5-19 A ribbon model of lysozyme
71. Fig. 5-19a A ribbon model of lysozyme (a) Groove
72. Fig. 5-19b (b) A space-filling model of lysozyme Groove
73. The sequence of amino acids determines a
74. Fig. 5-20 Antibody protein Protein from flu virus
75. Four Levels of Protein Structure The primary
76. Primary structure, the sequence of amino acids
77. Fig. 5-21 Primary Structure Secondary Structure Tertiary
78. Fig. 5-21a Amino acid subunits +H3N
79. Fig. 5-21b Amino acid subunits +H3N
80. The coils and folds of secondary structure
81. Fig. 5-21c Secondary Structure  pleated sheet Examples of amino acid subunits  helix
82. Fig. 5-21d Abdominal glands of the spider
83. Tertiary structure is determined by interactions between
84. Fig. 5-21e Tertiary Structure Quaternary Structure
85. Fig. 5-21f Polypeptide backbone Hydrophobic interactions and
86. Fig. 5-21g Polypeptide chain  Chains Heme Iron  Chains Collagen Hemoglobin
87. Quaternary structure results when two or more
88. Sickle-Cell Disease: A Change in Primary
89. Fig. 5-22 Primary structure Secondary and tertiary
90. Fig. 5-22a Primary structure Secondary and tertiary
91. Fig. 5-22b Primary structure Secondary and tertiary
92. Fig. 5-22c Normal red blood cells are
93. What Determines Protein Structure? In addition to
94. Fig. 5-23 Normal protein Denatured protein Denaturation Renaturation
95. Protein Folding in the Cell It is
96. Fig. 5-24 Hollow cylinder
97. Fig. 5-24a Hollow cylinder Chaperonin (fully assembled) Cap
98. Fig. 5-24b Correctly folded
99. Scientists use X-ray crystallography to determine a
100. Fig. 5-25 EXPERIMENT RESULTS X-ray
101. Fig. 5-25a Diffracted X-rays EXPERIMENT X-ray
102. Fig. 5-25b RESULTS RNA RNA polymerase II DNA
103. Concept 5.5: Nucleic acids store and transmit
104. The Roles of Nucleic Acids There are
105. Fig. 5-26-1 mRNA Synthesis of mRNA in the nucleus DNA NUCLEUS CYTOPLASM 1
106. Fig. 5-26-2 mRNA Synthesis of mRNA
107. Fig. 5-26-3 mRNA Synthesis of mRNA
108. The Structure of Nucleic Acids Nucleic acids
109. Fig. 5-27 5 end Nucleoside Nitrogenous base
110. Fig. 5-27ab 5' end 5'C 3'C 5'C
111. Fig. 5-27c-1 (c) Nucleoside components: nitrogenous bases
112. Fig. 5-27c-2 Ribose (in RNA) Deoxyribose (in DNA) Sugars (c) Nucleoside components: sugars
113. Nucleotide Monomers Nucleoside = nitrogenous base +
114. Nucleotide Polymers Nucleotide polymers are linked together
115. The DNA Double Helix A DNA molecule
116. Fig. 5-28 Sugar-phosphate backbones 3' end 3'
117. DNA and Proteins as Tape Measures of
118. The Theme of Emergent Properties in the
119. Fig. 5-UN2
120. Fig. 5-UN2a
121. Fig. 5-UN2b
122. Fig. 5-UN3 % of glycosidic linkages broken 100 50 0 Time
123. Fig. 5-UN4
124. Fig. 5-UN5
125. Fig. 5-UN6
126. Fig. 5-UN7
127. Fig. 5-UN8
128. Fig. 5-UN9
129. Fig. 5-UN10
130. You should now be able to: List
131. You should now be able to: Distinguish

Overview: The Molecules of Life All living things are made up of four classes of large biological molecules: carbohydrates, lipids, proteins, and nucleic acids Within cells, small organic molecules are joined

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The Structure and Function of Large Biological Molecules

Слайд 1Chapter 5
The Structure and Function of Large Biological Molecules

Слайд 2Overview: The Molecules of Life
All living things are made up of

four classes of large biological molecules: carbohydrates, lipids, proteins, and nucleic acids
Within cells, small organic molecules are joined together to form larger molecules
Macromolecules are large molecules composed of thousands of covalently connected atoms
Molecular structure and function are inseparable

Слайд 3Fig. 5-1

Слайд 4Concept 5.1: Macromolecules are polymers, built from monomers
A polymer is a

long molecule consisting of many similar building blocks
These small building-block molecules are called monomers
Three of the four classes of life’s organic molecules are polymers:
Carbohydrates
Proteins
Nucleic acids

Слайд 5A condensation reaction or more specifically a dehydration reaction occurs when

two monomers bond together through the loss of a water molecule
Enzymes are macromolecules that speed up the dehydration process
Polymers are disassembled to monomers by hydrolysis, a reaction that is essentially the reverse of the dehydration reaction

The Synthesis and Breakdown of Polymers

Animation: Polymers

Слайд 6Fig. 5-2
Short polymer
HO
1
2
3
H
HO
H
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
HO
H2O
H
1
2
3
4
Longer

polymer

(a) Dehydration reaction in the synthesis of a polymer

H2O

Hydrolysis adds a water
molecule, breaking a bond

(b) Hydrolysis of a polymer

Слайд 7Fig. 5-2a
Dehydration removes a water
molecule, forming a new bond
Short polymer
Unlinked monomer
Longer

polymer

Dehydration reaction in the synthesis of a polymer

H2O

(a)

Слайд 8Fig. 5-2b
Hydrolysis adds a water
molecule, breaking a bond
Hydrolysis of a polymer
HO
HO
HO
H2O
H
H
H
3
2
1
1
2
3
4
(b)

Слайд 9The Diversity of Polymers
Each cell has thousands of different kinds of

macromolecules
Macromolecules vary among cells of an organism, vary more within a species, and vary even more between species
An immense variety of polymers can be built from a small set of monomers

Слайд 10Concept 5.2: Carbohydrates serve as fuel and building material
Carbohydrates include sugars

and the polymers of sugars
The simplest carbohydrates are monosaccharides, or single sugars
Carbohydrate macromolecules are polysaccharides, polymers composed of many sugar building blocks

Слайд 11Sugars
Monosaccharides have molecular formulas that are usually multiples of CH2O
Glucose (C6H12O6)

is the most common monosaccharide
Monosaccharides are classified by
The location of the carbonyl group (as aldose or ketose)
The number of carbons in the carbon skeleton

Слайд 12Fig. 5-3
Dihydroxyacetone
Ribulose
Ketoses
Aldoses
Fructose
Glyceraldehyde
Ribose
Glucose
Galactose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 13Fig. 5-3a
Aldoses
Glyceraldehyde
Ribose
Glucose
Galactose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 14Fig. 5-3b
Ketoses
Dihydroxyacetone
Ribulose
Fructose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 15Though often drawn as linear skeletons, in aqueous solutions many sugars

form rings
Monosaccharides serve as a major fuel for cells and as raw material for building molecules

Слайд 16Fig. 5-4
(a) Linear and ring forms
(b) Abbreviated ring structure

Слайд 17Fig. 5-4a
(a) Linear and ring forms

Слайд 18Fig. 5-4b
(b) Abbreviated ring structure

Слайд 19A disaccharide is formed when a dehydration reaction joins two monosaccharides

This covalent bond is called a glycosidic linkage

Animation: Disaccharides

Слайд 20Fig. 5-5
(b) Dehydration reaction in the synthesis of sucrose
Glucose
Fructose
Sucrose
Maltose
Glucose
Glucose
(a) Dehydration reaction

in the synthesis of maltose

1–4
glycosidic
linkage

1–2
glycosidic
linkage

Слайд 21Polysaccharides
Polysaccharides, the polymers of sugars, have storage and structural roles
The structure

and function of a polysaccharide are determined by its sugar monomers and the positions of glycosidic linkages

Слайд 22Storage Polysaccharides
Starch, a storage polysaccharide of plants, consists entirely of glucose

monomers
Plants store surplus starch as granules within chloroplasts and other plastids

Слайд 23Fig. 5-6
(b) Glycogen: an animal polysaccharide
Starch
Glycogen
Amylose
Chloroplast
(a) Starch: a plant polysaccharide
Amylopectin
Mitochondria
Glycogen granules
0.5

µm

1 µm

Слайд 24Glycogen is a storage polysaccharide in animals
Humans and other vertebrates store

glycogen mainly in liver and muscle cells

Слайд 25Structural Polysaccharides
The polysaccharide cellulose is a major component of the tough

wall of plant cells
Like starch, cellulose is a polymer of glucose, but the glycosidic linkages differ
The difference is based on two ring forms for glucose: alpha (α) and beta (β)

Animation: Polysaccharides

Слайд 26Fig. 5-7
(a)  and  glucose
ring structures
 Glucose


Glucose

(b) Starch: 1–4 linkage of  glucose monomers

(b) Cellulose: 1–4 linkage of  glucose monomers

Слайд 27Fig. 5-7a
(a)  and  glucose ring structures
 Glucose


Glucose

Слайд 28Fig. 5-7bc
(b) Starch: 1–4 linkage of  glucose monomers
(c) Cellulose: 1–4

linkage of  glucose monomers

Слайд 29Polymers with α glucose are helical
Polymers with β glucose are straight
In

straight structures, H atoms on one strand can bond with OH groups on other strands
Parallel cellulose molecules held together this way are grouped into microfibrils, which form strong building materials for plants

Слайд 30Fig. 5-8
Glucose
monomer
Cellulose
molecules
Microfibril
Cellulose
microfibrils
in a plant
cell wall
0.5 µm

10 µm

Cell walls

Слайд 31Enzymes that digest starch by hydrolyzing α linkages can’t hydrolyze β

linkages in cellulose
Cellulose in human food passes through the digestive tract as insoluble fiber
Some microbes use enzymes to digest cellulose
Many herbivores, from cows to termites, have symbiotic relationships with these microbes

Слайд 32Fig. 5-9

Слайд 33Chitin, another structural polysaccharide, is found in the exoskeleton of arthropods
Chitin

also provides structural support for the cell walls of many fungi

Слайд 34Fig. 5-10
The structure
of the chitin
monomer.
(a)

(b)

(c)

Chitin forms the
exoskeleton of
arthropods.
Chitin is used to

make
a strong and flexible
surgical thread.

Слайд 35Concept 5.3: Lipids are a diverse group of hydrophobic molecules
Lipids are

the one class of large biological molecules that do not form polymers
The unifying feature of lipids is having little or no affinity for water
Lipids are hydrophobic because they consist mostly of hydrocarbons, which form nonpolar covalent bonds
The most biologically important lipids are fats, phospholipids, and steroids

Слайд 36Fats
Fats are constructed from two types of smaller molecules: glycerol and

fatty acids
Glycerol is a three-carbon alcohol with a hydroxyl group attached to each carbon
A fatty acid consists of a carboxyl group attached to a long carbon skeleton

Слайд 37Fig. 5-11
Fatty acid
(palmitic acid)
Glycerol
(a) Dehydration reaction in the synthesis of a

fat

Ester linkage

(b) Fat molecule (triacylglycerol)

Слайд 38Fig. 5-11a
Fatty acid
(palmitic acid)
(a)

Dehydration reaction in the synthesis of a fat
Glycerol

Слайд 39Fig. 5-11b
(b)

Fat molecule (triacylglycerol)
Ester linkage

Слайд 40Fats separate from water because water molecules form hydrogen bonds with

each other and exclude the fats
In a fat, three fatty acids are joined to glycerol by an ester linkage, creating a triacylglycerol, or triglyceride

Слайд 41Fatty acids vary in length (number of carbons) and in the

number and locations of double bonds
Saturated fatty acids have the maximum number of hydrogen atoms possible and no double bonds
Unsaturated fatty acids have one or more double bonds

Animation: Fats

Слайд 42Fig. 5-12
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

(b) Unsaturated fat

cis double
bond causes
bending

Слайд 43Fig. 5-12a
(a)

Saturated fat
Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid

Слайд 44Fig. 5-12b
(b)

Unsaturated fat
Structural formula
of an unsaturated
fat molecule
Oleic acid, an
unsaturated
fatty acid
cis double
bond

causes
bending

Слайд 45Fats made from saturated fatty acids are called saturated fats, and

are solid at room temperature
Most animal fats are saturated
Fats made from unsaturated fatty acids are called unsaturated fats or oils, and are liquid at room temperature
Plant fats and fish fats are usually unsaturated

Слайд 46A diet rich in saturated fats may contribute to cardiovascular disease

through plaque deposits
Hydrogenation is the process of converting unsaturated fats to saturated fats by adding hydrogen
Hydrogenating vegetable oils also creates unsaturated fats with trans double bonds
These trans fats may contribute more than saturated fats to cardiovascular disease

Слайд 47The major function of fats is energy storage
Humans and other mammals

store their fat in adipose cells
Adipose tissue also cushions vital organs and insulates the body

Слайд 48Phospholipids
In a phospholipid, two fatty acids and a phosphate group are

attached to glycerol
The two fatty acid tails are hydrophobic, but the phosphate group and its attachments form a hydrophilic head

Слайд 49Fig. 5-13
(b)

Space-filling model
(a)

(c)

Structural formula
Phospholipid symbol
Fatty acids
Hydrophilic
head
Hydrophobic
tails
Choline
Phosphate
Glycerol
Hydrophobic tails
Hydrophilic head

Слайд 50Fig. 5-13ab
(b)

Space-filling model
(a)

Structural formula
Fatty acids
Choline
Phosphate
Glycerol
Hydrophobic tails
Hydrophilic head

Слайд 51When phospholipids are added to water, they self-assemble into a bilayer,

with the hydrophobic tails pointing toward the interior
The structure of phospholipids results in a bilayer arrangement found in cell membranes
Phospholipids are the major component of all cell membranes

Слайд 52Fig. 5-14
Hydrophilic
head
Hydrophobic
tail
WATER
WATER

Слайд 53Steroids
Steroids are lipids characterized by a carbon skeleton consisting of four

fused rings
Cholesterol, an important steroid, is a component in animal cell membranes
Although cholesterol is essential in animals, high levels in the blood may contribute to cardiovascular disease

Слайд 54Fig. 5-15

Слайд 55Concept 5.4: Proteins have many structures, resulting in a wide range

of functions

Proteins account for more than 50% of the dry mass of most cells
Protein functions include structural support, storage, transport, cellular communications, movement, and defense against foreign substances

Слайд 56Table 5-1

Слайд 57Animation: Structural Proteins
Animation: Storage Proteins
Animation: Transport Proteins
Animation: Receptor Proteins
Animation: Contractile Proteins
Animation:

Defensive Proteins

Animation: Hormonal Proteins

Animation: Sensory Proteins

Animation: Gene Regulatory Proteins

Слайд 58Enzymes are a type of protein that acts as a catalyst

to speed up chemical reactions
Enzymes can perform their functions repeatedly, functioning as workhorses that carry out the processes of life

Animation: Enzymes

Слайд 59Fig. 5-16
Enzyme
(sucrase)
Substrate
(sucrose)
Fructose
Glucose
OH
H
O
H2O

Слайд 60Polypeptides
Polypeptides are polymers built from the same set of 20 amino

acids
A protein consists of one or more polypeptides

Слайд 61Amino Acid Monomers
Amino acids are organic molecules with carboxyl and amino

groups
Amino acids differ in their properties due to differing side chains, called R groups

Слайд 62Fig. 5-UN1
Amino
group
Carboxyl
group
 carbon

Слайд 63Fig. 5-17
Nonpolar
Glycine
(Gly or G)
Alanine
(Ala or A)
Valine
(Val or V)
Leucine
(Leu or L)
Isoleucine
(Ile or

Methionine
(Met or M)

Phenylalanine
(Phe or F)

Trypotphan
(Trp or W)

Proline
(Pro or P)

Polar

Serine
(Ser or S)

Threonine
(Thr or T)

Cysteine
(Cys or C)

Tyrosine
(Tyr or Y)

Asparagine
(Asn or N)

Glutamine
(Gln or Q)

Electrically
charged

Acidic

Basic

Aspartic acid
(Asp or D)

Glutamic acid
(Glu or E)

Lysine
(Lys or K)

Arginine
(Arg or R)

Histidine
(His or H)

Слайд 64Fig. 5-17a
Nonpolar
Glycine
(Gly or G)
Alanine
(Ala or A)
Valine
(Val or V)
Leucine

(Leu or L)

Isoleucine
(Ile or I)

Methionine
(Met or M)

Phenylalanine
(Phe or F)

Tryptophan
(Trp or W)

Proline
(Pro or P)

Слайд 65Fig. 5-17b
Polar
Asparagine
(Asn or N)
Glutamine
(Gln or Q)
Serine
(Ser or S)
Threonine

(Thr or T)

Cysteine
(Cys or C)

Tyrosine
(Tyr or Y)

Слайд 66Fig. 5-17c
Acidic
Arginine
(Arg or R)
Histidine
(His or H)
Aspartic acid
(Asp or

Glutamic acid
(Glu or E)

Lysine
(Lys or K)

Basic

Electrically
charged

Слайд 67Amino Acid Polymers
Amino acids are linked by peptide bonds
A polypeptide is

a polymer of amino acids
Polypeptides range in length from a few to more than a thousand monomers
Each polypeptide has a unique linear sequence of amino acids

Слайд 68Peptide
bond
Fig. 5-18
Amino end
(N-terminus)

Peptide
bond
Side chains
Backbone

Carboxyl end
(C-terminus)
(a)
(b)

Слайд 69Protein Structure and Function
A functional protein consists of one or more

polypeptides twisted, folded, and coiled into a unique shape

Слайд 70Fig. 5-19
A ribbon model of lysozyme
(a)
(b)
A space-filling model of lysozyme
Groove
Groove

Слайд 71Fig. 5-19a
A ribbon model of lysozyme
(a)
Groove

Слайд 72Fig. 5-19b
(b)
A space-filling model of lysozyme
Groove

Слайд 73The sequence of amino acids determines a protein’s three-dimensional structure
A protein’s

structure determines its function

Слайд 74Fig. 5-20
Antibody protein
Protein from flu virus

Слайд 75Four Levels of Protein Structure
The primary structure of a protein is

its unique sequence of amino acids
Secondary structure, found in most proteins, consists of coils and folds in the polypeptide chain
Tertiary structure is determined by interactions among various side chains (R groups)
Quaternary structure results when a protein consists of multiple polypeptide chains

Animation: Protein Structure Introduction

Слайд 76Primary structure, the sequence of amino acids in a protein, is

like the order of letters in a long word
Primary structure is determined by inherited genetic information

Animation: Primary Protein Structure

Слайд 77Fig. 5-21
Primary
Structure
Secondary
Structure
Tertiary
Structure
 pleated sheet
Examples of
amino acid
subunits
+H3N
Amino end
 helix
Quaternary
Structure

Слайд 78
Fig. 5-21a
Amino acid
subunits
+H3N
Amino end
25
20
15
10
5
1
Primary Structure

Слайд 79Fig. 5-21b
Amino acid
subunits
+H3N
Amino end
Carboxyl end
125
120
115
110
105
100
95
90
85
80
75
20
25
15
10
5
1

Слайд 80The coils and folds of secondary structure result from hydrogen bonds

between repeating constituents of the polypeptide backbone
Typical secondary structures are a coil called an α helix and a folded structure called a β pleated sheet

Animation: Secondary Protein Structure

Слайд 81
Fig. 5-21c
Secondary Structure
 pleated sheet
Examples of
amino acid
subunits
 helix

Слайд 82Fig. 5-21d
Abdominal glands of the
spider secrete silk fibers
made of a structural

protein
containing  pleated sheets.

The radiating strands, made
of dry silk fibers, maintain
the shape of the web.

The spiral strands (capture
strands) are elastic, stretching
in response to wind, rain,
and the touch of insects.

Слайд 83Tertiary structure is determined by interactions between R groups, rather than

interactions between backbone constituents
These interactions between R groups include hydrogen bonds, ionic bonds, hydrophobic interactions, and van der Waals interactions
Strong covalent bonds called disulfide bridges may reinforce the protein’s structure

Animation: Tertiary Protein Structure

Слайд 84

Fig. 5-21e
Tertiary Structure
Quaternary Structure

Слайд 85Fig. 5-21f
Polypeptide
backbone
Hydrophobic
interactions and
van der Waals
interactions
Disulfide bridge
Ionic bond
Hydrogen
bond

Слайд 86Fig. 5-21g
Polypeptide
chain
 Chains
Heme
Iron
 Chains
Collagen
Hemoglobin

Слайд 87Quaternary structure results when two or more polypeptide chains form one

macromolecule
Collagen is a fibrous protein consisting of three polypeptides coiled like a rope
Hemoglobin is a globular protein consisting of four polypeptides: two alpha and two beta chains

Animation: Quaternary Protein Structure

Слайд 88Sickle-Cell Disease: A Change in Primary Structure
A slight change in primary

structure can affect a protein’s structure and ability to function
Sickle-cell disease, an inherited blood disorder, results from a single amino acid substitution in the protein hemoglobin

Слайд 89Fig. 5-22
Primary
structure
Secondary
and tertiary
structures
Quaternary
structure
Normal
hemoglobin
(top view)
Primary
structure
Secondary
and tertiary
structures
Quaternary
structure
Function
Function
 subunit
Molecules do
not associate
with one
another; each
carries oxygen.
Red

blood
cell shape

Normal red blood
cells are full of
individual
hemoglobin
moledules, each
carrying oxygen.

10 µm

Normal hemoglobin





Val

His

Leu

Thr

Pro

Glu

Red blood
cell shape

 subunit

Exposed
hydrophobic
region

Sickle-cell
hemoglobin





Molecules
interact with
one another and
crystallize into
a fiber; capacity
to carry oxygen
is greatly reduced.





Fibers of abnormal
hemoglobin deform
red blood cell into
sickle shape.

10 µm

Sickle-cell hemoglobin

Glu

Pro

Thr

Leu

His

Val

Слайд 90Fig. 5-22a
Primary
structure
Secondary
and tertiary
structures
Function
Quaternary
structure
Molecules do
not associate
with one
another; each
carries oxygen.
Normal
hemoglobin
(top view)
 subunit
Normal hemoglobin
7
6
5
4
3
2
1




Glu
Val
His
Leu
Thr
Pro
Glu

Слайд 91Fig. 5-22b
Primary
structure
Secondary
and tertiary
structures
Function
Quaternary
structure
Molecules
interact with
one another and
crystallize into
a fiber;

capacity
to carry oxygen
is greatly reduced.

Sickle-cell
hemoglobin

 subunit

Sickle-cell hemoglobin







Val

His

Leu

Thr

Pro

Glu

Exposed
hydrophobic
region

Слайд 92Fig. 5-22c
Normal red blood
cells are full of
individual
hemoglobin
molecules, each
carrying oxygen.
Fibers of

abnormal
hemoglobin deform
red blood cell into
sickle shape.

10 µm

Слайд 93What Determines Protein Structure?
In addition to primary structure, physical and chemical

conditions can affect structure
Alterations in pH, salt concentration, temperature, or other environmental factors can cause a protein to unravel
This loss of a protein’s native structure is called denaturation
A denatured protein is biologically inactive

Слайд 94Fig. 5-23
Normal protein
Denatured protein
Denaturation
Renaturation

Слайд 95Protein Folding in the Cell
It is hard to predict a protein’s

structure from its primary structure
Most proteins probably go through several states on their way to a stable structure
Chaperonins are protein molecules that assist the proper folding of other proteins

Слайд 96

Fig. 5-24
Hollow
cylinder
Cap
Chaperonin
(fully assembled)

Polypeptide
Steps of Chaperonin
Action:
An unfolded poly-
peptide enters the
cylinder from one

end.

The cap attaches, causing the
cylinder to change shape in
such a way that it creates a
hydrophilic environment for
the folding of the polypeptide.

The cap comes
off, and the properly
folded protein is
released.

Correctly
folded
protein

Слайд 97Fig. 5-24a
Hollow
cylinder
Chaperonin
(fully assembled)
Cap

Слайд 98

Fig. 5-24b
Correctly
folded
protein
Polypeptide
Steps of Chaperonin
Action:
1
2
An unfolded poly-
peptide enters the
cylinder from one end.
The

cap attaches, causing the
cylinder to change shape in
such a way that it creates a
hydrophilic environment for
the folding of the polypeptide.

The cap comes
off, and the properly
folded protein is
released.

Слайд 99Scientists use X-ray crystallography to determine a protein’s structure
Another method is

nuclear magnetic resonance (NMR) spectroscopy, which does not require protein crystallization
Bioinformatics uses computer programs to predict protein structure from amino acid sequences

Слайд 100

Fig. 5-25
EXPERIMENT
RESULTS
X-ray
source
X-ray
beam
Diffracted
X-rays
Crystal
Digital detector
X-ray diffraction
pattern
RNA
polymerase II
RNA
DNA

$Fig. 5-25EXPERIMENTRESULTSX-raysourceX-raybeamDiffractedX-raysCrystalDigital detectorX-ray diffractionpatternRNApolymerase IIRNADNA$

Слайд 101
Fig. 5-25a
Diffracted
X-rays
EXPERIMENT
X-ray
source
X-ray
beam
Crystal
Digital detector
X-ray diffraction
pattern

$Fig. 5-25aDiffractedX-raysEXPERIMENTX-raysourceX-raybeamCrystalDigital detectorX-ray diffractionpattern$

Слайд 102
Fig. 5-25b
RESULTS
RNA
RNA
polymerase II
DNA

Слайд 103Concept 5.5: Nucleic acids store and transmit hereditary information
The amino acid

sequence of a polypeptide is programmed by a unit of inheritance called a gene
Genes are made of DNA, a nucleic acid

Слайд 104The Roles of Nucleic Acids
There are two types of nucleic acids:
Deoxyribonucleic

acid (DNA)
Ribonucleic acid (RNA)
DNA provides directions for its own replication
DNA directs synthesis of messenger RNA (mRNA) and, through mRNA, controls protein synthesis
Protein synthesis occurs in ribosomes

Слайд 105
Fig. 5-26-1
mRNA
Synthesis of
mRNA in the
nucleus
DNA
NUCLEUS
CYTOPLASM
1

Слайд 106
Fig. 5-26-2
mRNA
Synthesis of
mRNA in the
nucleus
DNA
NUCLEUS
mRNA
CYTOPLASM
Movement of
mRNA into cytoplasm
via nuclear pore

1
2

Слайд 107
Fig. 5-26-3
mRNA
Synthesis of
mRNA in the
nucleus
DNA
NUCLEUS
mRNA
CYTOPLASM
Movement of
mRNA into cytoplasm
via nuclear pore
Ribosome
Amino
acids
Polypeptide
Synthesis
of protein

1
2
3

Слайд 108The Structure of Nucleic Acids
Nucleic acids are polymers called polynucleotides
Each polynucleotide

is made of monomers called nucleotides
Each nucleotide consists of a nitrogenous base, a pentose sugar, and a phosphate group
The portion of a nucleotide without the phosphate group is called a nucleoside

Слайд 109Fig. 5-27
5 end
Nucleoside
Nitrogenous
base

Phosphate
group
Sugar
(pentose)
(b) Nucleotide
(a) Polynucleotide, or nucleic acid
3 end
3C
3C
5C
5C
Nitrogenous bases
Pyrimidines
Cytosine (C)
Thymine

(T, in DNA)

Uracil (U, in RNA)

Purines

Adenine (A)

Guanine (G)

Sugars

Deoxyribose (in DNA)

Ribose (in RNA)

Слайд 110Fig. 5-27ab
5' end
5'C
3'C
5'C
3'C
3' end
(a) Polynucleotide, or nucleic acid
(b) Nucleotide
Nucleoside
Nitrogenous
base

3'C
5'C
Phosphate
group
Sugar
(pentose)

Слайд 111Fig. 5-27c-1
(c) Nucleoside components: nitrogenous bases
Purines
Guanine (G)
Adenine (A)
Cytosine (C)
Thymine (T, in

DNA)

Uracil (U, in RNA)

Nitrogenous bases

Pyrimidines

Слайд 112Fig. 5-27c-2
Ribose (in RNA)
Deoxyribose (in DNA)
Sugars
(c) Nucleoside components: sugars

Слайд 113Nucleotide Monomers
Nucleoside = nitrogenous base + sugar
There are two families of

nitrogenous bases:
Pyrimidines (cytosine, thymine, and uracil) have a single six-membered ring
Purines (adenine and guanine) have a six-membered ring fused to a five-membered ring
In DNA, the sugar is deoxyribose; in RNA, the sugar is ribose
Nucleotide = nucleoside + phosphate group

Слайд 114Nucleotide Polymers
Nucleotide polymers are linked together to build a polynucleotide
Adjacent nucleotides

are joined by covalent bonds that form between the –OH group on the 3′ carbon of one nucleotide and the phosphate on the 5′ carbon on the next
These links create a backbone of sugar-phosphate units with nitrogenous bases as appendages
The sequence of bases along a DNA or mRNA polymer is unique for each gene

Слайд 115The DNA Double Helix
A DNA molecule has two polynucleotides spiraling around

an imaginary axis, forming a double helix
In the DNA double helix, the two backbones run in opposite 5′ → 3′ directions from each other, an arrangement referred to as antiparallel
One DNA molecule includes many genes
The nitrogenous bases in DNA pair up and form hydrogen bonds: adenine (A) always with thymine (T), and guanine (G) always with cytosine (C)

Слайд 116Fig. 5-28
Sugar-phosphate
backbones
3' end
3' end
3' end
3' end
5' end
5' end
5' end
5' end
Base pair

(joined by
hydrogen bonding)

Old strands

New
strands

Nucleotide
about to be
added to a
new strand

Слайд 117DNA and Proteins as Tape Measures of Evolution
The linear sequences of

nucleotides in DNA molecules are passed from parents to offspring
Two closely related species are more similar in DNA than are more distantly related species
Molecular biology can be used to assess evolutionary kinship

Слайд 118The Theme of Emergent Properties in the Chemistry of Life: A

Review

Higher levels of organization result in the emergence of new properties
Organization is the key to the chemistry of life

Слайд 119Fig. 5-UN2

Слайд 120Fig. 5-UN2a

Слайд 121Fig. 5-UN2b

Слайд 122Fig. 5-UN3
% of glycosidic
linkages broken
100
50
0
Time

Слайд 123Fig. 5-UN4

Слайд 124Fig. 5-UN5

Слайд 125Fig. 5-UN6

Слайд 126Fig. 5-UN7

Слайд 127Fig. 5-UN8

Слайд 128Fig. 5-UN9

Слайд 129Fig. 5-UN10

Слайд 130You should now be able to:
List and describe the four major

classes of molecules
Describe the formation of a glycosidic linkage and distinguish between monosaccharides, disaccharides, and polysaccharides
Distinguish between saturated and unsaturated fats and between cis and trans fat molecules
Describe the four levels of protein structure

Слайд 131You should now be able to:
Distinguish between the following pairs: pyrimidine

and purine, nucleotide and nucleoside, ribose and deoxyribose, the 5′ end and 3′ end of a nucleotide

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The Structure and Function of Large Biological Molecules презентация

Содержание

Слайд 1Chapter 5The Structure and Function of Large Biological Molecules

Слайд 2Overview: The Molecules of LifeAll living things are made up of

Слайд 3Fig. 5-1

Слайд 4Concept 5.1: Macromolecules are polymers, built from monomersA polymer is a

Слайд 5A condensation reaction or more specifically a dehydration reaction occurs when

Слайд 6Fig. 5-2Short polymerHO123HHOHUnlinked monomerDehydration removes a watermolecule, forming a new bondHOH2OH1234Longer

Слайд 7Fig. 5-2aDehydration removes a watermolecule, forming a new bondShort polymerUnlinked monomerLonger

Слайд 8Fig. 5-2bHydrolysis adds a watermolecule, breaking a bondHydrolysis of a polymerHOHOHOH2OHHH3211234(b)

Слайд 9The Diversity of PolymersEach cell has thousands of different kinds of

Слайд 10Concept 5.2: Carbohydrates serve as fuel and building materialCarbohydrates include sugars

Слайд 11SugarsMonosaccharides have molecular formulas that are usually multiples of CH2OGlucose (C6H12O6)

Слайд 12Fig. 5-3DihydroxyacetoneRibuloseKetosesAldosesFructoseGlyceraldehydeRiboseGlucoseGalactoseHexoses (C6H12O6)Pentoses (C5H10O5)Trioses (C3H6O3)

Слайд 13Fig. 5-3aAldosesGlyceraldehydeRiboseGlucoseGalactoseHexoses (C6H12O6)Pentoses (C5H10O5)Trioses (C3H6O3)

Слайд 14Fig. 5-3bKetosesDihydroxyacetoneRibuloseFructoseHexoses (C6H12O6)Pentoses (C5H10O5)Trioses (C3H6O3)

Слайд 15Though often drawn as linear skeletons, in aqueous solutions many sugars

Слайд 16Fig. 5-4(a) Linear and ring forms(b) Abbreviated ring structure

Слайд 17Fig. 5-4a(a) Linear and ring forms

Слайд 18Fig. 5-4b(b) Abbreviated ring structure

Слайд 19A disaccharide is formed when a dehydration reaction joins two monosaccharides

Слайд 20Fig. 5-5(b) Dehydration reaction in the synthesis of sucroseGlucoseFructoseSucroseMaltoseGlucoseGlucose(a) Dehydration reaction

Слайд 21PolysaccharidesPolysaccharides, the polymers of sugars, have storage and structural rolesThe structure

Слайд 22Storage PolysaccharidesStarch, a storage polysaccharide of plants, consists entirely of glucose

Слайд 23Fig. 5-6(b) Glycogen: an animal polysaccharideStarchGlycogenAmyloseChloroplast(a) Starch: a plant polysaccharideAmylopectinMitochondriaGlycogen granules0.5

Слайд 24Glycogen is a storage polysaccharide in animalsHumans and other vertebrates store

Слайд 25Structural PolysaccharidesThe polysaccharide cellulose is a major component of the tough

Слайд 26Fig. 5-7(a)  and  glucose ring structures Glucose

Слайд 27Fig. 5-7a(a)  and  glucose ring structures  Glucose 

Слайд 28Fig. 5-7bc(b) Starch: 1–4 linkage of  glucose monomers(c) Cellulose: 1–4

Слайд 29Polymers with α glucose are helicalPolymers with β glucose are straightIn

Слайд 30Fig. 5-8 GlucosemonomerCellulosemoleculesMicrofibrilCellulosemicrofibrilsin a plantcell wall0.5 µm10 µmCell walls

Слайд 31Enzymes that digest starch by hydrolyzing α linkages can’t hydrolyze β

Слайд 32Fig. 5-9

Слайд 33Chitin, another structural polysaccharide, is found in the exoskeleton of arthropodsChitin

Слайд 34Fig. 5-10The structureof the chitinmonomer.(a)(b)(c)Chitin forms theexoskeleton ofarthropods.Chitin is used to

Слайд 35Concept 5.3: Lipids are a diverse group of hydrophobic moleculesLipids are

Слайд 36FatsFats are constructed from two types of smaller molecules: glycerol and

Слайд 37Fig. 5-11Fatty acid(palmitic acid)Glycerol(a) Dehydration reaction in the synthesis of a

Слайд 38Fig. 5-11aFatty acid(palmitic acid)(a)Dehydration reaction in the synthesis of a fatGlycerol

Слайд 39Fig. 5-11b(b)Fat molecule (triacylglycerol)Ester linkage

Слайд 40Fats separate from water because water molecules form hydrogen bonds with

Слайд 41Fatty acids vary in length (number of carbons) and in the

Слайд 42Fig. 5-12Structuralformula of asaturated fatmoleculeStearic acid, asaturated fattyacid(a) Saturated fatStructural formulaof

Слайд 43Fig. 5-12a(a)Saturated fatStructuralformula of asaturated fatmoleculeStearic acid, asaturated fattyacid

Слайд 44Fig. 5-12b(b)Unsaturated fatStructural formulaof an unsaturatedfat moleculeOleic acid, anunsaturatedfatty acidcis doublebond

Слайд 45Fats made from saturated fatty acids are called saturated fats, and

Слайд 46A diet rich in saturated fats may contribute to cardiovascular disease

Слайд 47The major function of fats is energy storageHumans and other mammals

Слайд 48PhospholipidsIn a phospholipid, two fatty acids and a phosphate group are

Слайд 49Fig. 5-13(b)Space-filling model(a)(c)Structural formulaPhospholipid symbolFatty acidsHydrophilicheadHydrophobictailsCholinePhosphateGlycerolHydrophobic tailsHydrophilic head

Слайд 50Fig. 5-13ab(b)Space-filling model(a)Structural formulaFatty acidsCholinePhosphateGlycerolHydrophobic tailsHydrophilic head

Слайд 51When phospholipids are added to water, they self-assemble into a bilayer,

Слайд 52Fig. 5-14HydrophilicheadHydrophobictailWATERWATER

Слайд 53SteroidsSteroids are lipids characterized by a carbon skeleton consisting of four

Слайд 54Fig. 5-15

Слайд 55Concept 5.4: Proteins have many structures, resulting in a wide range

Слайд 56Table 5-1

Слайд 57Animation: Structural ProteinsAnimation: Storage ProteinsAnimation: Transport ProteinsAnimation: Receptor ProteinsAnimation: Contractile ProteinsAnimation:

Слайд 58Enzymes are a type of protein that acts as a catalyst

Слайд 59Fig. 5-16Enzyme(sucrase)Substrate(sucrose)FructoseGlucoseOHHOH2O

Слайд 60PolypeptidesPolypeptides are polymers built from the same set of 20 amino

Слайд 61Amino Acid MonomersAmino acids are organic molecules with carboxyl and amino

Слайд 62Fig. 5-UN1AminogroupCarboxylgroup carbon

Слайд 63Fig. 5-17NonpolarGlycine(Gly or G)Alanine(Ala or A)Valine(Val or V)Leucine(Leu or L)Isoleucine(Ile or

Слайд 64Fig. 5-17aNonpolarGlycine (Gly or G)Alanine (Ala or A)Valine (Val or V)Leucine

Слайд 65Fig. 5-17bPolarAsparagine (Asn or N)Glutamine (Gln or Q)Serine (Ser or S)Threonine

Слайд 66Fig. 5-17cAcidicArginine (Arg or R)Histidine (His or H)Aspartic acid (Asp or

Слайд 67Amino Acid PolymersAmino acids are linked by peptide bondsA polypeptide is

Слайд 68PeptidebondFig. 5-18Amino end(N-terminus)PeptidebondSide chainsBackboneCarboxyl end(C-terminus)(a)(b)

Слайд 69Protein Structure and FunctionA functional protein consists of one or more

Слайд 70Fig. 5-19A ribbon model of lysozyme(a)(b)A space-filling model of lysozymeGrooveGroove

Слайд 71Fig. 5-19aA ribbon model of lysozyme(a)Groove

Слайд 72Fig. 5-19b(b)A space-filling model of lysozymeGroove

Слайд 73The sequence of amino acids determines a protein’s three-dimensional structureA protein’s

Слайд 74Fig. 5-20Antibody proteinProtein from flu virus

Слайд 75Four Levels of Protein StructureThe primary structure of a protein is

Слайд 76Primary structure, the sequence of amino acids in a protein, is

Слайд 77Fig. 5-21PrimaryStructureSecondaryStructureTertiaryStructure pleated sheetExamples ofamino acidsubunits+H3N Amino end helixQuaternaryStructure

Слайд 78Fig. 5-21aAmino acidsubunits+H3N Amino end2520151051Primary Structure

Слайд 1Chapter 5
The Structure and Function of Large Biological Molecules

Слайд 2Overview: The Molecules of Life
All living things are made up of

Слайд 4Concept 5.1: Macromolecules are polymers, built from monomers
A polymer is a

Слайд 6Fig. 5-2
Short polymer
HO
1
2
3
H
HO
H
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
HO
H2O
H
1
2
3
4
Longer

Слайд 7Fig. 5-2a
Dehydration removes a water
molecule, forming a new bond
Short polymer
Unlinked monomer
Longer

Слайд 8Fig. 5-2b
Hydrolysis adds a water
molecule, breaking a bond
Hydrolysis of a polymer
HO
HO
HO
H2O
H
H
H
3
2
1
1
2
3
4
(b)

Слайд 9The Diversity of Polymers
Each cell has thousands of different kinds of

Слайд 10Concept 5.2: Carbohydrates serve as fuel and building material
Carbohydrates include sugars

Слайд 11Sugars
Monosaccharides have molecular formulas that are usually multiples of CH2O
Glucose (C6H12O6)

Слайд 12Fig. 5-3
Dihydroxyacetone
Ribulose
Ketoses
Aldoses
Fructose
Glyceraldehyde
Ribose
Glucose
Galactose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 13Fig. 5-3a
Aldoses
Glyceraldehyde
Ribose
Glucose
Galactose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 14Fig. 5-3b
Ketoses
Dihydroxyacetone
Ribulose
Fructose
Hexoses (C6H12O6)
Pentoses (C5H10O5)
Trioses (C3H6O3)

Слайд 16Fig. 5-4
(a) Linear and ring forms
(b) Abbreviated ring structure

Слайд 17Fig. 5-4a
(a) Linear and ring forms

Слайд 18Fig. 5-4b
(b) Abbreviated ring structure

Слайд 20Fig. 5-5
(b) Dehydration reaction in the synthesis of sucrose
Glucose
Fructose
Sucrose
Maltose
Glucose
Glucose
(a) Dehydration reaction

Слайд 21Polysaccharides
Polysaccharides, the polymers of sugars, have storage and structural roles
The structure

Слайд 22Storage Polysaccharides
Starch, a storage polysaccharide of plants, consists entirely of glucose

Слайд 23Fig. 5-6
(b) Glycogen: an animal polysaccharide
Starch
Glycogen
Amylose
Chloroplast
(a) Starch: a plant polysaccharide
Amylopectin
Mitochondria
Glycogen granules
0.5

Слайд 24Glycogen is a storage polysaccharide in animals
Humans and other vertebrates store

Слайд 25Structural Polysaccharides
The polysaccharide cellulose is a major component of the tough

Слайд 26Fig. 5-7
(a)  and  glucose
ring structures
 Glucose


Слайд 27Fig. 5-7a
(a)  and  glucose ring structures
 Glucose


Слайд 28Fig. 5-7bc
(b) Starch: 1–4 linkage of  glucose monomers
(c) Cellulose: 1–4

Слайд 29Polymers with α glucose are helical
Polymers with β glucose are straight
In

Слайд 30Fig. 5-8
Glucose
monomer
Cellulose
molecules
Microfibril
Cellulose
microfibrils
in a plant
cell wall
0.5 µm

10 µm

Cell walls

Слайд 33Chitin, another structural polysaccharide, is found in the exoskeleton of arthropods
Chitin

Слайд 34Fig. 5-10
The structure
of the chitin
monomer.
(a)

(b)

(c)

Chitin forms the
exoskeleton of
arthropods.
Chitin is used to

Слайд 35Concept 5.3: Lipids are a diverse group of hydrophobic molecules
Lipids are

Слайд 36Fats
Fats are constructed from two types of smaller molecules: glycerol and

Слайд 37Fig. 5-11
Fatty acid
(palmitic acid)
Glycerol
(a) Dehydration reaction in the synthesis of a

Слайд 38Fig. 5-11a
Fatty acid
(palmitic acid)
(a)

Dehydration reaction in the synthesis of a fat
Glycerol

Слайд 39Fig. 5-11b
(b)

Fat molecule (triacylglycerol)
Ester linkage

Слайд 42Fig. 5-12
Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid
(a) Saturated fat
Structural formula
of

Слайд 43Fig. 5-12a
(a)

Saturated fat
Structural
formula of a
saturated fat
molecule
Stearic acid, a
saturated fatty
acid

Слайд 44Fig. 5-12b
(b)

Unsaturated fat
Structural formula
of an unsaturated
fat molecule
Oleic acid, an
unsaturated
fatty acid
cis double
bond

Слайд 47The major function of fats is energy storage
Humans and other mammals

Слайд 48Phospholipids
In a phospholipid, two fatty acids and a phosphate group are

Слайд 49Fig. 5-13
(b)

Space-filling model
(a)

(c)

Structural formula
Phospholipid symbol
Fatty acids
Hydrophilic
head
Hydrophobic
tails
Choline
Phosphate
Glycerol
Hydrophobic tails
Hydrophilic head

Слайд 50Fig. 5-13ab
(b)

Space-filling model
(a)

Structural formula
Fatty acids
Choline
Phosphate
Glycerol
Hydrophobic tails
Hydrophilic head

Слайд 52Fig. 5-14
Hydrophilic
head
Hydrophobic
tail
WATER
WATER

Слайд 53Steroids
Steroids are lipids characterized by a carbon skeleton consisting of four

Слайд 57Animation: Structural Proteins
Animation: Storage Proteins
Animation: Transport Proteins
Animation: Receptor Proteins
Animation: Contractile Proteins
Animation:

Слайд 59Fig. 5-16
Enzyme
(sucrase)
Substrate
(sucrose)
Fructose
Glucose
OH
H
O
H2O

Слайд 60Polypeptides
Polypeptides are polymers built from the same set of 20 amino

Слайд 61Amino Acid Monomers
Amino acids are organic molecules with carboxyl and amino

Слайд 62Fig. 5-UN1
Amino
group
Carboxyl
group
 carbon

Слайд 63Fig. 5-17
Nonpolar
Glycine
(Gly or G)
Alanine
(Ala or A)
Valine
(Val or V)
Leucine
(Leu or L)
Isoleucine
(Ile or

Слайд 64Fig. 5-17a
Nonpolar
Glycine
(Gly or G)
Alanine
(Ala or A)
Valine
(Val or V)
Leucine

Слайд 65Fig. 5-17b
Polar
Asparagine
(Asn or N)
Glutamine
(Gln or Q)
Serine
(Ser or S)
Threonine

Слайд 66Fig. 5-17c
Acidic
Arginine
(Arg or R)
Histidine
(His or H)
Aspartic acid
(Asp or

Слайд 67Amino Acid Polymers
Amino acids are linked by peptide bonds
A polypeptide is

Слайд 68Peptide
bond
Fig. 5-18
Amino end
(N-terminus)

Peptide
bond
Side chains
Backbone

Carboxyl end
(C-terminus)
(a)
(b)

Слайд 69Protein Structure and Function
A functional protein consists of one or more

Слайд 70Fig. 5-19
A ribbon model of lysozyme
(a)
(b)
A space-filling model of lysozyme
Groove
Groove

Слайд 71Fig. 5-19a
A ribbon model of lysozyme
(a)
Groove

Слайд 72Fig. 5-19b
(b)
A space-filling model of lysozyme
Groove

Слайд 73The sequence of amino acids determines a protein’s three-dimensional structure
A protein’s

Слайд 74Fig. 5-20
Antibody protein
Protein from flu virus

Слайд 75Four Levels of Protein Structure
The primary structure of a protein is

Слайд 77Fig. 5-21
Primary
Structure
Secondary
Structure
Tertiary
Structure
 pleated sheet
Examples of
amino acid
subunits
+H3N
Amino end
 helix
Quaternary
Structure

Слайд 78
Fig. 5-21a
Amino acid
subunits
+H3N
Amino end
25
20
15
10
5
1
Primary Structure

Слайд 79Fig. 5-21b
Amino acid
subunits
+H3N
Amino end
Carboxyl end
125
120
115
110
105
100
95
90
85
80
75
20
25
15
10
5
1

Слайд 81
Fig. 5-21c
Secondary Structure
 pleated sheet
Examples of
amino acid
subunits
 helix

Слайд 82Fig. 5-21d
Abdominal glands of the
spider secrete silk fibers
made of a structural

Слайд 84

Fig. 5-21e
Tertiary Structure
Quaternary Structure

Слайд 85Fig. 5-21f
Polypeptide
backbone
Hydrophobic
interactions and
van der Waals
interactions
Disulfide bridge
Ionic bond
Hydrogen
bond

Слайд 86Fig. 5-21g
Polypeptide
chain
 Chains
Heme
Iron
 Chains
Collagen
Hemoglobin

Слайд 88Sickle-Cell Disease: A Change in Primary Structure
A slight change in primary

Слайд 89Fig. 5-22
Primary
structure
Secondary
and tertiary
structures
Quaternary
structure
Normal
hemoglobin
(top view)
Primary
structure
Secondary
and tertiary
structures
Quaternary
structure
Function
Function
 subunit
Molecules do
not associate
with one
another; each
carries oxygen.
Red

Слайд 90Fig. 5-22a
Primary
structure
Secondary
and tertiary
structures
Function
Quaternary
structure
Molecules do
not associate
with one
another; each
carries oxygen.
Normal
hemoglobin
(top view)
 subunit
Normal hemoglobin
7
6
5
4
3
2
1




Glu
Val
His
Leu
Thr
Pro
Glu

Слайд 91Fig. 5-22b
Primary
structure
Secondary
and tertiary
structures
Function
Quaternary
structure
Molecules
interact with
one another and
crystallize into
a fiber;

Слайд 92Fig. 5-22c
Normal red blood
cells are full of
individual
hemoglobin
molecules, each
carrying oxygen.
Fibers of

Слайд 93What Determines Protein Structure?
In addition to primary structure, physical and chemical

Слайд 94Fig. 5-23
Normal protein
Denatured protein
Denaturation
Renaturation

Слайд 95Protein Folding in the Cell
It is hard to predict a protein’s

Слайд 96

Fig. 5-24
Hollow
cylinder
Cap
Chaperonin
(fully assembled)

Polypeptide
Steps of Chaperonin
Action:
An unfolded poly-
peptide enters the
cylinder from one

Слайд 97Fig. 5-24a
Hollow
cylinder
Chaperonin
(fully assembled)
Cap

Слайд 98

Fig. 5-24b
Correctly
folded
protein
Polypeptide
Steps of Chaperonin
Action:
1
2
An unfolded poly-
peptide enters the
cylinder from one end.
The

Слайд 99Scientists use X-ray crystallography to determine a protein’s structure
Another method is