Title: Biochemistry 153A
1Biochemistry 153A
- Professor Richard L. Weiss
- Fall 2009
2INTRODUCTION
3BiochemistryThe Study of Life on the Molecular
Level
- Bio Life
- Chemistry Property of Molecules
4What You Will Learn
- Composition , structures and functions of
proteins, carbohydrates, and lipids - Principles of enzyme catalysis
- Central metabolic pathways of energy transduction
- Beginning of an understanding of the integrated
picture of life and its basis in chemistry.
5Principles of Enzyme Catalysis
- The role of proteins as enzymes
- Enzyme kinetics
- Catalytic mechanisms
- Regulation of enzyme catalysis
6Central Metabolic Pathways of Energy Transduction
- Glycolysis
- Tricarboxylic Acid Cycle(TCA Cycle Krebs Cycle
Citric Acid Cycle) - Electron Transport Chain
- Oxidative Phosphorylation
7Properties of Life(Norman Horowitz)
- Replication
- Catalysis
- MutabilityOrganisms
8Cells(Basis for Life)
- Prokaryotes lack nucleus
- Eucaryotes membrane-enclosed nucleus
9Procaryotes(e.g. Escherichia coli)
- Adapted to fluctuating environments
10Procaryote Shapes
Figure 1-7
11Procaryote Structure
Figure 1-6
12Metabolic Energy Sources
- Autotrophs (self-feeding) synthesize all
cellular constituents - Chemolithotrophs oxidation of inorganic
compounds - Photoautotrophs photosynthesis
- Heterotrophs (other-feeding) dependent on
autotrophs - oxidation of organic compounds - Obligate aerobes
- Facultative anaerobes
- Obligate anaerobes
13Eucaryotes(e.g. Saccharomyces cerevisiae or
human cells)
- Adapted to stable environments
14Eucaryotes(Differences with Procaryotes)
- Increased complexity gt10,000 rxns vs. 3,000
rxns - Increased size 103 106 x volume
- Smaller surfacevolume ratio
- Membrane-enclosed organelles
- Increased solvent capacity
- Increased membrane surface
- Compartmentation
15Eucaryotic Cell Structure
Figure 1-8
16Evolutionary Relationships
Figure 1-9
17Fundamental Similarity of Biological Processes
18Advantages of Studying Microorganisms
- Ethics
- Availability of large numbers of identical
individuals - Ease of manipulation
- Genetics
- Molecular Biology
- Inexpensive
19Principles of Biochemistry
- Genetic Hypothesis
- Central Dogma (of Molecular Biology)
- Enzyme Hypothesis
- Energy Hypothesis
- Spontaneous Self-Assembly Hypothesis
20Genetic Hypothesis
DNA as the Genetic Material
21Central Dogma(of Molelcular Biology)
Figure 3-13
22Enzyme Hypothesis
23Energy Hypothesis(Biological Transformations)
- Catabolism exergonic oxidation
- Anabolism endergonic processes
24Anabolism and Catabolism(Heterotrophs)
25ATP
26Sources of ATP
- Phototrophs photosynthesis
- Chemotrophs oxidation of organic compounds
(e.g. carbohydrates, lipids, and proteins)
27Figure 1-11
28Spontaneous Self-Assembly Hypothesis
29Characteristics of Biomolecules
- Self-Replication
- Self-Assembly
- Self-Regulation
30Self-Replication(Based on Templates)
Complementarity
31Complementarity within Molecules
Figure 1-5
32Self-Assembly
- Micromolecules gt Macromolecules
- Macromolecules gt Macromolecular Assemblies
33Self-Regulation
34Thermodynamics versus Kinetics
35Complexity of Biomolecules
- Requirement for Structural Diversity
36Composition of a Typical Bacterial Cell
Simply learning structures appears to be a
monumental task!
37Principle of Structural Simplicity
38Biopolymers
- Types
- Homopolymers
- Heteropolymers
- Length and Branching
- Linear homopolymers
- Branched homopolymers
- Linear heteropolymers
- Branched heteropolymers
39Homopolymers
Linear Homopolymer
Branched Homopolymer
40Heteropolymers
Linear Heteropolymer
Branched Heteropolymer
41Biological Macromolecules
42Proteins(Amino Acids)
Only 20 naturally-occurring amino acids Only
linear structures
43Polysaccharides(Sugars)
Only a few sugars (8) Linear and branched
molecules
44Lipids (Various Precursors)Neutral Lipids
45Lipids (Various Precursors)Phospholipids
46Nucleic Acids(Nucleotides)
47Combinations
- e.g.
- Glycoproteins
- Glycolipids
48Macromolecules are composed of polymers of a few
simple precursor molecules
49Structural Diversity
50Proteins
- aa1aa2aa3aan
- Number of structures 20n
- 100 amino acids per molecule
- 20100 molecules
51Nucleic Acids
- N1N2N3Nn
- Number of structures 4n
- 1,000,000 nucleotides per DNA molecule
- 41,000,000 molecules!!!
52Polysaccharides
- Homopolymers and Heteropolymers
- Many different sugar molecules
- Linear and branched
- Many different molecules!!!
53Lipids
- Many complex molecules!!!
54Simple construction provides an immense number of
possible structures fully capable of providing
the necessary diversity required for life.