《分子生物学》课程PPT教学课件（讲义）蛋白质结构

蛩白质结构 Protein structure

蛋白质结构 Protein structure

Properties of Proteins o Proteins Have Many Different Biological Functions Enzymes Transport Proteins Nutrient and Storage Proteins Contractile or Motile proteins Structural proteins a Defense proteins Regulatory Proteins Other proteins

Properties of Proteins Proteins Have Many Different Biological Functions ◼ Enzymes ◼ Transport Proteins ◼ Nutrient and Storage Proteins ◼ Contractile or Motile Proteins ◼ Structural Proteins ◼ Defense Proteins ◼ Regulatory Proteins ◼ Other Proteins

Enzyme Functions of proteins. The light produced by fireflies is the result of a light-producing reaction involving luciferin and ATP that is catalyzed by the enzyme luciferase

Functions of proteins. The light produced by fireflies is the result of a light-producing reaction involving luciferin and ATP that is catalyzed by the enzyme luciferase Enzyme

Transport Proteins Erythrocytes contain large amounts of the oxygen-transporting protein hemoglobin

Transport Proteins Erythrocytes contain large amounts of the oxygen-transporting protein hemoglobin

Contractile or motile proteins The movement of cilia in protozoans depends on the action of the protein dynein

The movement of cilia in protozoans depends on the action of the protein dynein Contractile or Motile Proteins

Structural proteins The protein fibroin is the major structural component of spider webs

Structural Proteins The protein fibroin is the major structural component of spider webs

Defense proteins Castor beans contain a highly toxic protein called ricin

Castor beans contain a highly toxic protein called ricin. Defense Proteins

Proteins Are very Large Molecules Table 6-1 Molecular data on some proteins Number of Molecular Number of polypeptide weight residues chains Insulin (bovine 5,733 51 Cytochrome c(human) 13.000 104 Ribonuclease A (bovine pancreas) 13,700 124 Lysozyme (egg white) 13.90 129 Myoglobin (equine heart) 16.890 153 Chymotrypsin (bovine pancrea 21600 241 3 Chymotrypsinogen (bovine 22.000 245 Hemoglobin (human) 64500 574 Serum albumin (human) 68500 550 Hexokinase (yeast) 102000 800 Immunoglobulin G(humani 145.000 20 RNA polymerase (E coln 450000 4,100 Apolipoprotein B (human) 513.000 4536 Glutamate dehydrogenase L.000.000 8.300 (bovine liver

Proteins Are Very Large Molecules

Proteins have Characteristic mino acid Compositions Table 6-2 Amino acid composition of two proteins Number of residues per molecule of prot Human Bovine cytochrome c chymotrypsinogen A GIn GGH uys 625322833868 245800632094 Phe 6 Pro snTy 3342715 238435 Total 104

Proteins Have Characteristic Amino Acid Compositions

Some Proteins Contain Chemica/ Groups 0如er7 han amino acids Table 6-3 Conjugated proteins Clans Prosthetic group Example apoproteins Lipids BrLaipoprotein of blood Glycoproteins Carbohydrates Immunoglobulin G Phosphoproteins Phosphate groups Casein of milk Hemoproteins Heme (iron porphyrin) Hemoglobin Flavoproteins Flavin nucleotides Succinate dehydrogenase Metalloproteins Ferritin nc Alcohol dehydrogenase Calcium calmodulin Molybdenum Dinitrogenase oppe Plastocyanin

Some Proteins Contain Chemical Groups Other Than Amino Acids