Transcript Fatty acid
HO 1 2 3 H Short polymer HO Unlinked monomer Dehydration removes a water molecule, forming a new bond HO 2 1 H 3 H2O 4 H Longer polymer (a) Dehydration reaction in the synthesis of a polymer HO 1 2 3 4 Hydrolysis adds a water molecule, breaking a bond HO 1 2 3 H H H2O HO H (b) Hydrolysis of a polymer 1 Trioses (C3H6O3) Pentoses (C5H10O5) Hexoses (C6H12O6) Glyceraldehyde Ribose Glucose Galactose Dihydroxyacetone Ribulose Fructose 2 (a) Linear and ring forms (b) Abbreviated ring structure 3 1–4 glycosidic linkage Glucose Glucose Maltose (a) Dehydration reaction in the synthesis of maltose 1–2 glycosidic linkage Glucose Fructose Sucrose (b) Dehydration reaction in the synthesis of sucrose 4 Chloroplast Mitochondria Glycogen granules Starch 0.5 µm 1 µm Glycogen Amylose Amylopectin (a) Starch: a plant polysaccharide (b) Glycogen: an animal polysaccharide 5 (a) and glucose ring structures Glucose (b) Starch: 1–4 linkage of glucose monomers Glucose (b) Cellulose: 1–4 linkage of glucose monomers 6 Cell walls Cellulose microfibrils in a plant cell wall Microfibril 10 µm 0.5 µm Cellulose molecules Glucose monomer 7 8 (a) The structure of the chitin monomer. (b) Chitin forms the exoskeleton of arthropods. (c) Chitin is used to make a strong and flexible surgical thread. 9 Fatty acid (palmitic acid) Glycerol (a) Dehydration reaction in the synthesis of a fat Ester linkage (b) Fat molecule (triacylglycerol) 10 Structural formula of a saturated fat molecule Stearic acid, a saturated fatty acid (a) Saturated fat Structural formula of an unsaturated fat molecule Oleic acid, an unsaturated fatty acid (b) Unsaturated fat cis double bond causes bending 11 Hydrophilic head Hydrophobic tails (a) Structural formula Choline Phosphate Glycerol Fatty acids Hydrophilic head Hydrophobic tails (b) Space-filling model (c) Phospholipid symbol 12 Hydrophilic head Hydrophobic tail WATER WATER 13 14 15 Substrate (sucrose) Glucose OH Enzyme (sucrase) H2O Fructose HO 16 carbon Amino group Carboxyl group 17 Nonpolar Glycine (Gly or G) Valine (Val or V) Alanine (Ala or A) Methionine (Met or M) Leucine (Leu or L) Trypotphan (Trp or W) Phenylalanine (Phe or F) Isoleucine (Ile or I) Proline (Pro or P) Polar Serine (Ser or S) Threonine (Thr or T) Cysteine (Cys or C) Tyrosine (Tyr or Y) Asparagine Glutamine (Asn or N) (Gln or Q) Electrically charged Acidic Aspartic acid Glutamic acid (Glu or E) (Asp or D) Basic Lysine (Lys or K) Arginine (Arg or R) Histidine (His or H) 18 Peptide bond (a) Side chains Peptide bond Backbone (b) Amino end (N-terminus) Carboxyl end (C-terminus) 19 Groove Groove (a) A ribbon model of lysozyme (b) A space-filling model of lysozyme 20 Antibody protein Protein from flu virus 21 Primary Structure Secondary Structure Tertiary Structure Quaternary Structure pleated sheet +H N 3 Amino end Examples of amino acid subunits helix 22 Hydrophobic interactions and van der Waals interactions Polypeptide backbone Hydrogen bond Disulfide bridge Ionic bond 23 Polypeptide chain Chains Iron Heme Chains Hemoglobin Collagen 24 Normal hemoglobin Primary structure Val His Leu Thr Pro Glu Glu 1 2 3 4 5 6 7 Secondary and tertiary structures subunit Function Normal hemoglobin (top view) Secondary and tertiary structures 1 2 3 Normal red blood cells are full of individual hemoglobin moledules, each carrying oxygen. 6 7 subunit Sickle-cell hemoglobin Function Molecules interact with one another and crystallize into a fiber; capacity to carry oxygen is greatly reduced. 10 µm Red blood cell shape 5 Exposed hydrophobic region Molecules do not associate with one another; each carries oxygen. 4 Quaternary structure Val His Leu Thr Pro Val Glu Quaternary structure Sickle-cell hemoglobin Primary structure 10 µm Red blood cell shape Fibers of abnormal hemoglobin deform red blood cell into sickle shape. 25 Denaturation Normal protein Renaturation Denatured protein 26 Polypeptide Correctly folded protein Cap Hollow cylinder Chaperonin (fully assembled) Steps of Chaperonin 2 Action: 1 An unfolded polypeptide enters the cylinder from one end. The cap attaches, causing the 3 The cap comes cylinder to change shape in off, and the properly such a way that it creates a folded protein is hydrophilic environment for released. the folding of the polypeptide. 27 DNA 1 Synthesis of mRNA in the nucleus mRNA NUCLEUS CYTOPLASM mRNA 2 Movement of mRNA into cytoplasm via nuclear pore Ribosome 3 Synthesis of protein Polypeptide Amino acids 28 5 end Nitrogenous bases Pyrimidines 5C 3C Nucleoside Nitrogenous base Cytosine (C) Thymine (T, in DNA) Uracil (U, in RNA) Purines Phosphate group 5C Sugar (pentose) Adenine (A) Guanine (G) (b) Nucleotide 3C Sugars 3 end (a) Polynucleotide, or nucleic acid Deoxyribose (in DNA) Ribose (in RNA) (c) Nucleoside components: sugars 29 5' end 3' end Sugar-phosphate backbones Base pair (joined by hydrogen bonding) Old strands Nucleotide about to be added to a new strand 3' end 5' end New strands 5' end 3' end 5' end 3' end 30 31