《生物化学》课程PPT教学课件（英文版）Chapter 3 The Same 20 Amino Acids Serve as Building Blocks for All Proteins in Nature

Chapter 3 The Same 20 Amino Acids Serve as Building blocks for All Proteins in Nature Homework 2 part 1: Ch 5 problems 2, 9, 12, 16

Chapter 3 The Same 20 Amino Acids Serve as Building Blocks for All Proteins in Nature Homework 2 part 1: Ch. 5 problems 2, 9, 12, 16

1. Proteins are extremely versatile in function and crucial in virtually all biological processes. 1.1 Almost all chemical reactions occurring in living organisms are catalyzed by enzymes. 1.1.1 Many thousands of enzymes have been discovered, each catalyzing a different kind of chemical reaction 1. 1.2 Life would not occur without enzyme catalysis. 1.1.3 Enzymes are the most varied and most highly specialized proteins

1.1 Almost all chemical reactions occurring in living organisms are catalyzed by enzymes. 1.1.1 Many thousands of enzymes have been discovered, each catalyzing a different kind of chemical reaction. 1.1.2 Life would not occur without enzyme catalysis. 1.1.3 Enzymes are the most varied and most highly specialized proteins. 1. Proteins are extremely versatile in function and crucial in virtually all biological processes

1.2 Many small molecules and ions are transported by specific proteins. 1.2. 1 Some proteins transport molecules from one organ to another, many exist in the blood plasma, e.g., hemoglobin(oxygen), serum albumin (fatty acids), lipoproteins (lipids), and transferrin (iron). 1.2.2 Some proteins transport molecules across plasma membrane or organelle membranes (glucose, amino acids, nucleotides, chloride, potassium, sodium ions but not water)

1.2 Many small molecules and ions are transported by specific proteins. 1.2.1 Some proteins transport molecules from one organ to another, many exist in the blood plasma, e.g., hemoglobin (oxygen), serum albumin (fatty acids), lipoproteins (lipids), and transferrin (iron). 1.2.2 Some proteins transport molecules across plasma membrane or organelle membranes (glucose, amino acids, nucleotides, chloride, potassium, sodium ions but not water)

1.3 Some proteins function as nutrient or storage proteins. For example, many of such kind exist in plant seeds, animal eggs(Ovalbumin of egg white, casein of milk). Ferritin in animal tissue function to store ion(about 4500 ions are stored in the cavity of each ferritin complex 1. 4 Some proteins are responsible for the coordinated motions(contraction, changing shape, moving about). For example, actin and myosin in muscle and nonmuscle cells. Tubulin and dynein in eukaryotic flagella and cilia

1.3 Some proteins function as nutrient or storage proteins. For example, many of such kind exist in plant seeds, animal eggs (Ovalbumin of egg white, casein of milk). Ferritin in animal tissue function to store ion (about 4500 ions are stored in the cavity of each ferritin complex!). 1.4 Some proteins are responsible for the coordinated motions (contraction, changing shape, moving about). For example, actin and myosin in muscle and nonmuscle cells. Tubulin and dynein in eukaryotic flagella and cilia

1.5 Some proteins are responsible for mechanical support (strength and protection) 5 I Collagen in tendons(筋腱), cartilage, and leather. 152 Elastin in ligaments(韧带) 1.5.3 Keratin in hair, fingernails, feathers 1.5.4 Fibroin in silk fibers and spider webs 1.5.5 Resilin in wing hinges of some insects

1.5 Some proteins are responsible for mechanical support (strength and protection) 1.5.1 Collagen in tendons (筋腱), cartilage, and leather. 1.5.2 Elastin in ligaments (韧带). 1.5.3 Keratin in hair, fingernails, feathers. 1.5.4 Fibroin in silk fibers and spider webs. 1.5.5 Resilin in wing hinges of some insects

1. 6 Some proteins function to defend the organisms 1.6.1 Immunoglobins in vertebrates 1.6.2 Fibrinogen and thrombin in blood-clotting 1.6.3 Snake venom. bacterial toxins. and toxic plant proteins (ricin). 1. 7 Some proteins help regulate cellular or physiological activity 1.7.1 Growth factors and transcription factors regulate cell growth and differentiation 1.7.2 Hormones(e.g, insulin, growth hormon) coordinate activities of different cells in multicellular organisms

1.6 Some proteins function to defend the organisms 1.6.1 Immunoglobins in vertebrates 1.6.2 Fibrinogen and thrombin in blood-clotting 1.6.3 Snake venom, bacterial toxins, and toxic plant proteins (ricin). 1.7 Some proteins help regulate cellular or physiological activity 1.7.1 Growth factors and transcription factors regulate cell growth and differentiation 1.7.2 Hormones (e.g., insulin, growth hormon) coordinate activities of different cells in multicellular organisms

1. 8 Some proteins are responsible for the generation and transmission of nerve impulses. 1.8.1 Rhodopsin responses to light to generate vision 1.8.2 Acetylcholine receptor are responsible for transmitting nerve impulses ar synapses 1.9 Many proteins have other functions. Antifreeze proteins protect the blood of Antarctic fish from freezing. Special heat stable proteins in thermophile bacteria

1.8 Some proteins are responsible for the generation and transmission of nerve impulses. 1.8.1 Rhodopsin responses to light to generate vision 1.8.2 Acetylcholine receptor are responsible for transmitting nerve impulses at synapses 1.9 Many proteins have other functions. Antifreeze proteins protect the blood of Antarctic fish from freezing. Special heat stable proteins in thermophile bacteria

Chymotrypsin with its active site

Chymotrypsin with its active site

Fireflies emit light catalyzed by luciferase with ATP

Fireflies emit light catalyzed by luciferase with ATP

(b) Erythrocytes contain a large amount of hemoglobins, the oxygen-transporting protein

Erythrocytes contain a large amount of hemoglobins, the oxygen-transporting protein