Biochemistry 153A - PowerPoint PPT Presentation

1 / 54
About This Presentation
Title:

Biochemistry 153A

Description:

Composition , structures and functions of proteins, ... (TCA Cycle; Krebs Cycle; Citric Acid Cycle) Electron Transport Chain. Oxidative Phosphorylation ... – PowerPoint PPT presentation

Number of Views:29
Avg rating:3.0/5.0
Slides: 55
Provided by: chemist87
Category:

less

Transcript and Presenter's Notes

Title: Biochemistry 153A


1
Biochemistry 153A
  • Professor Richard L. Weiss
  • Fall 2009

2
INTRODUCTION
3
BiochemistryThe Study of Life on the Molecular
Level
  • Bio Life
  • Chemistry Property of Molecules

4
What 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.

5
Principles of Enzyme Catalysis
  • The role of proteins as enzymes
  • Enzyme kinetics
  • Catalytic mechanisms
  • Regulation of enzyme catalysis

6
Central Metabolic Pathways of Energy Transduction
  • Glycolysis
  • Tricarboxylic Acid Cycle(TCA Cycle Krebs Cycle
    Citric Acid Cycle)
  • Electron Transport Chain
  • Oxidative Phosphorylation

7
Properties of Life(Norman Horowitz)
  • Replication
  • Catalysis
  • MutabilityOrganisms

8
Cells(Basis for Life)
  • Prokaryotes lack nucleus
  • Eucaryotes membrane-enclosed nucleus

9
Procaryotes(e.g. Escherichia coli)
  • Adapted to fluctuating environments

10
Procaryote Shapes
Figure 1-7
11
Procaryote Structure
Figure 1-6
12
Metabolic 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

13
Eucaryotes(e.g. Saccharomyces cerevisiae or
human cells)
  • Adapted to stable environments

14
Eucaryotes(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

15
Eucaryotic Cell Structure
Figure 1-8
16
Evolutionary Relationships
Figure 1-9
17
Fundamental Similarity of Biological Processes
  • Procaryotes
  • Eucaryotes

18
Advantages of Studying Microorganisms
  • Ethics
  • Availability of large numbers of identical
    individuals
  • Ease of manipulation
  • Genetics
  • Molecular Biology
  • Inexpensive

19
Principles of Biochemistry
  • Genetic Hypothesis
  • Central Dogma (of Molecular Biology)
  • Enzyme Hypothesis
  • Energy Hypothesis
  • Spontaneous Self-Assembly Hypothesis

20
Genetic Hypothesis
DNA as the Genetic Material
21
Central Dogma(of Molelcular Biology)
Figure 3-13
22
Enzyme Hypothesis
23
Energy Hypothesis(Biological Transformations)
  • Catabolism exergonic oxidation
  • Anabolism endergonic processes

24
Anabolism and Catabolism(Heterotrophs)
25
ATP
26
Sources of ATP
  • Phototrophs photosynthesis
  • Chemotrophs oxidation of organic compounds
    (e.g. carbohydrates, lipids, and proteins)

27
Figure 1-11
28
Spontaneous Self-Assembly Hypothesis
29
Characteristics of Biomolecules
  • Self-Replication
  • Self-Assembly
  • Self-Regulation

30
Self-Replication(Based on Templates)
Complementarity
31
Complementarity within Molecules
Figure 1-5
32
Self-Assembly
  • Micromolecules gt Macromolecules
  • Macromolecules gt Macromolecular Assemblies

33
Self-Regulation
34
Thermodynamics versus Kinetics
35
Complexity of Biomolecules
  • Requirement for Structural Diversity

36
Composition of a Typical Bacterial Cell
Simply learning structures appears to be a
monumental task!
37
Principle of Structural Simplicity
38
Biopolymers
  • Types
  • Homopolymers
  • Heteropolymers
  • Length and Branching
  • Linear homopolymers
  • Branched homopolymers
  • Linear heteropolymers
  • Branched heteropolymers

39
Homopolymers
Linear Homopolymer
Branched Homopolymer
40
Heteropolymers
Linear Heteropolymer
Branched Heteropolymer
41
Biological Macromolecules
42
Proteins(Amino Acids)
Only 20 naturally-occurring amino acids Only
linear structures
43
Polysaccharides(Sugars)
Only a few sugars (8) Linear and branched
molecules
44
Lipids (Various Precursors)Neutral Lipids
45
Lipids (Various Precursors)Phospholipids
46
Nucleic Acids(Nucleotides)
47
Combinations
  • e.g.
  • Glycoproteins
  • Glycolipids

48
Macromolecules are composed of polymers of a few
simple precursor molecules
49
Structural Diversity
50
Proteins
  • aa1aa2aa3aan
  • Number of structures 20n
  • 100 amino acids per molecule
  • 20100 molecules

51
Nucleic Acids
  • N1N2N3Nn
  • Number of structures 4n
  • 1,000,000 nucleotides per DNA molecule
  • 41,000,000 molecules!!!

52
Polysaccharides
  • Homopolymers and Heteropolymers
  • Many different sugar molecules
  • Linear and branched
  • Many different molecules!!!

53
Lipids
  • Many complex molecules!!!

54
Simple construction provides an immense number of
possible structures fully capable of providing
the necessary diversity required for life.
Write a Comment
User Comments (0)
About PowerShow.com