1. Introduction to Biochemistry Department of Biochemistry
Lecture 1
Introduction to Biochemistry
（生物化学）
Zhihong Li（李志红）
Department of Biochemistry

2. Introduction What is the Biochemistry? History and development
How to study Biochemistry?

3. 1. Biochemistry Definition: The chemistry of life
The science concerned with the chemical basis of life.
The science concerned with the various molecules that occur in living cells and organisms and with their chemical reaction.
Anything more than a superficial comprehension of life – in all its diverse manifestation - demands a knowledge of biochemistry.

4. Biochemistry
Aim: to describe and explain, in molecular terms, all chemical processes of living cells
Structure-function
Metabolism and Regulation
How life began？

5. Biochemistry
Significance: be essential to all life sciences as the common knowledge
Genetics; Cell biology; Molecular biology
Physiology and Immunology
Pharmacology and Pharmacy
Toxicology; Pathology; Microbiology
Zoology and Botany

6. Biochemistry
Medical students who acquire a sound knowledge of biochemistry will be in a strong position to deal with two central concerns of the health sciences:
(1) the understanding and maintenance of health
(2) the understanding and effective treatment of disease
Causes of cancers
Molecular lesions causing various genetic diseases
Rational design of new drugs

7. 2. History and development of Biochemistry
1903, Neuberg (German): “Biochemistry”
“Chemistry of Life”

8. Two notable breakthroughs
(1) Discovery of the role of enzymes as catalysts
(2) Identification of nucleic acids as information molecules
Flow of information: from nucleic acids to proteins
DNA RNA Protein

9. Some historic events
In 1937， Krebs for the discovery of the Citric Acid Cycle-won the Nobel Prize in Physiology or Medicine in 1953
In 1953，Watson & Crick for the discovery of the “DNA Double Helix” -won the Nobel Prize in Physiology or Medicine in 1962

10. In 1955，Sanger for the determination of insulin sequence- won the Nobel Prize in Physiology or Medicine in 1956
In 1980， Sanger & Gilbert for Sequencing of DNA-won the Nobel Prize in Chemistry in 1980
In 1993, Kary B. Mullis for invention of PCR method -won the Nobel Prize in Chemistry in 1993

11. Transgenic animal
Gene engineering
Clone
Green Fluorescence protein

12. HGP from 1990, completed in 2003

13. 3.What dose the Biochemistry discuss?
structure and function of cellular components
proteins, carbohydrates, lipids, nucleic acids and other biomolecules
Metabolism and Regulation
Gene expression and modulation
DNA RNA Protein

14. Polymers and Monomers
Each of these types of molecules are polymers that are assembled from single units called monomers.
Each type of macromolecule is an assemblage of a different type of monomer.

15. Macromolecule
Carbohydrates
Lipids
Proteins
Nucleic acids
Monomer
Monosaccharide
Not always polymers; Hydrocarbon chains
Amino acids
Nucleotides

16. How do monomers form polymers?
In condensation reactions (also called dehydration synthesis), a molecule of water is removed from two monomers as they are connected together.

17. 17

18. Building block Macromolecule Simple sugar Amino acid Nucleotide
Anabolic
Building block
Simple sugar
Amino acid
Nucleotide
Fatty acid
Macromolecule
Polysaccharide
Protein (peptide)
RNA or DNA
Lipid
Catabolic

19. Principles of Biochemistry
Cells (basic structural units of living organisms) are highly organized and constant source of energy is required to maintain the ordered state.
All organisms use the same type of molecules: carbohydrates, proteins, lipids & nucleic acids.
Living processes contain thousands of chemical pathways. Precise regulation and integration of these pathways are required to maintain life.
Instructions for growth, reproduction and developments for each organism is encoded in their DNA.

20. 4. Cells Basic building blocks of life
Smallest living unit of an organism
A cell may be an entire organism (unicellular) or it may be one of billions of cells that make up the organism (multicellular).
Grow, reproduce, use energy, adapt, respond to their environment
Many cannot be seen with the naked eye
a typical cell size is 10µm; a typical cell mass is 1 nanogram.)

21. Cells May be Prokaryotic or Eukaryotic
Prokaryotes (Greek: pro-before; karyon-nucleus) include various bacteria
lack a nucleus or membrane-bound structures called organelles
Eukaryotes (Greek: eu-true; karyon-nucleus) include most other cells (plants, fungi, & animals)
have a nucleus and membrane-bound organelles

22. •Cell membrane & cell wall
•Nucleoid region contains the DNA
Contain ribosomes (no membrane)
• Cell Membrane
• Nucleus
Cytoplasm with organelles

24. Characteristic Bio-membranes and Organelles
Plasma Membrane-Cell’s defining boundary Providing a barrier and containing transport and signaling systems.
Nucleus – Cell’s information center Double membrane surrounding the chromosomes and the nucleolus. The place where almost all DNA replication and RNA synthesis occur. The nucleolus is a site for synthesis of RNA making up the ribosome
Mitochondria- the power generators
Mitochondria (Greek: mitos-thread; chondros-granule): Surrounded by a double membrane with a series of folds called cristae. Functions in energy production through metabolism. Contains its own DNA.

25. Ribosomes Protein and RNA complex responsible for protein synthesis
Endoplasmic reticulum (ER) – The transport network for molecules
Rough endoplasmic reticulum (RER) Covered with ribosomes (causing the "rough" appearance) which are in the process of synthesizing proteins for secretion or localization in membranes.
Ribosomes Protein and RNA complex responsible for protein synthesis
Smooth endoplasmic reticulum (SER) A site for synthesis and metabolism of lipids.

26. Golgi apparatus -process and package the macromolecules
Golgi apparatus -process and package the macromolecules. A series of stacked membranes. Vesicles carry materials from the RER to the Golgi apparatus. Vesicles move between the stacks while the proteins are "processed" to a mature form.
Lysosomes-contain digestive enzyme A membrane bound organelle that is responsible for degrading proteins and membranes in the cell.
Cytoplasm enclosed by the plasma membrane, liquid portion called cytosol and it houses the membranous organelles.

27. 5. Biomolecules
Just like cells are building blocks of tissues, biomolecules are building blocks of cells.
Animal and plant cells contain approximately 10,000 kinds of biomolecules.
Water constitutes 50-95% of cells content by weight.
Ions like Na+, K+ and Ca2+ may account for another 1%.
Almost all other kinds of biomolecules are organic (C, H, N, O, P, S).
Organic compounds are compounds composed primarily of a Carbon skeleton.

28. Carbon
Carbon is more abundant in living organisms than it is in the rest of the universe.
What makes Carbon Special? Why is Carbon so different from all the other elements on the periodic table?
The answer derives from the ability of Carbon atoms to bond together to form long chains and rings.

29. Carbon can form immensely diverse compounds, from simple to complex.
DNA with tens of Billions of Carbon atoms
Methane with 1 Carbon atom

30. Biomolecules are compounds of carbon with a variety of functional groups
Some common functional groups of biomolecules. In this figure and throughout the book, we use R to represent “any substituent.” It may be as simple as a hydrogen atom, but typically it is a carbon-containing group. When two or more substituents are shown in a molecule, we designate them R1, R2, and so forth.

31. Types of biomolecules Small molecules: Monomers: Polymers:
Lipid, phospholipid, glycolipid, sterol,
Vitamin
Hormone, neurotransmitter
Carbohydrate, sugar
Monomers:
Amino acids
Nucleotides
Monosaccharides
Polymers:
Peptides, oligopeptides, polypeptides, proteins
Nucleic acids, i.e. DNA, RNA
Oligosaccharides, polysaccharides (including cellulose)

32. Chemical composition of a normal man (weight 65 kg)
Constituent
Percent (%)
Weight (kg)
Water
61.6 40
Protein
17.0 11
Lipid
13.8 9
Carbohydrate
1.5 1
Minerals
6.1 4

33. Structural hierarchy in the molecular organization of cells
Structural hierarchy in the molecular organization of cells. The nucleus of this plant cell is an organelle containing several types of supramolecular complexes, including chromatin. Chromatin consists of two types of macromolecules, DNA and many different proteins, each made up of simple subunits.

34. Similarities among all types of cells
All cells use nucleic acids (DNA) to store information
Except RNA viruses, but not true cells (incapable of autonomous replication)
All cells use nucleic acids (RNA) to access stored information
All cells use proteins as catalysts (enzymes) for chemical reactions
A few examples of RNA based enzymes, which may reflect primordial use of RNA
All cells use lipids for membrane components
Different types of lipids in different types of cells
All cells use carbohydrates for cell walls (if present), recognition, and energy generation 34

35. How much biochemistry do you need to know for this course?
Carbohydrates
Lipids
Proteins
Nucleic Acids
1. You are expected to learn the structure and functions of these organic compounds:
2. You will be expected to learn the basic biochemical processes of major cell functions, such as respiration, protein synthesis and so on.

36. Topics 1 Introduction , amino acid and protein (8h) 2
Nucleic acid: Structure and properties (4h) 3
Carbohydrates: Structure and properties (2h) 4
Vitamins and coenzymes (4h) 5
Enzymes (6h) 6
Metabolism of carbohydrates (8h) 7
Assessment 8
Bioenergetics (4h) 9
Metabolism of lipids (8h) 10
Metabolism of amino acids (6h) 11
Integration of metabolism and review(2h)

37. 6. Text book and references
U Satyanarayana, Biochemistry
Murray RK, Harper’s Illustrated Biochemistry, 26th ed.
Nelson DL and Cox MM. Lehninger Principles of Biochemistry, 5th ed

38. 7. Some tips for study of biochemistry
Inspiring interest, confidence
Previewing and reviewing freshly
Taking studying notes
Discussing in groups
Practice, crosstalk with other subjects
Making use of internet

39. Just do as some proverbs say:
“I hear, and I forget,
I see, and I remember,
I do, and I understand.”
“Practice makes perfect”
“No pains, no gains”

40. Final theory grade Final theory grade=
First Assessment: 30~35%
Final exam: 45~50%
Daily performance: 20%
Notice: 1/3 absent, can not take part in the final exam.