Biomolecules of the Central Dogma DNA  RNA  Protein

Nucleotide Structure

DNA vs. RNA Sugar (C2’) Single vs. Double Stranded –Stem-loop (Hairpin) Thymine vs. Uracil

Nucleic Acids Sugar phosphate backbone –5’ Phosphate –3’ Hydroxide Base Pairing Rules –Purine: A, G –Pyrimidine: C, U, T –A=T, G≡C

DNA Coiling to form Chromosomes

Protein: Primary Structure The sequence of amino acids N-terminus, C-terminus

Protein: Secondary Structure

β pleated sheet β barrel –A large beta-sheet that twists and coils to form a closed structure

Tertiary Structure 3D structure of a single protein molecule Folding is driven by chemical interactions of R groups:

Protein: Quaternary Structure Assembly of several protein subunits Stabilized by non-covalent interactions and disulfide bonds –Dimer, trimer, tetramer, multimer –“Homo” = same subunits –“Hetero” = different subunits

Metabolism Metabolic Direction WaterEnergyExamples Anabolic “Building up” CondensationUsedPhotosynthesis Polymerization DNA replication Transcription & Translation ADP + Pi  ATP Catabolic “Breaking down” HydrolysisReleasedDigestion Glycolysis/ Krebs Cycle Combustion ATP  ADP +Pi

Condensation Reactions (a.k.a. Dehydration Synthesis) Two monomers are joined together, with the loss of water. Synthesis of all the important biological macromolecules: –carbohydrates, proteins, lipids, nucleic acids

Protein Synthesis Polymers of amino acids linked by peptide bonds

Carbohydrate Synthesis Linked by glycosidic bonds –Ex) Di-, Tri-, Polysaccharides –Ex) Polymers of glucose form cellulose and starch.

Nucleic Acid Synthesis DNA/RNA strands  string of nucleotides joined together by phosphodiester bonds

Lipid Synthesis “Fats” are a subgroup of lipids called triglycerides  Ester linkage

Depicting Molecules in Space

Ribbon Diagrams (a.k.a. Richardson Diagrams) 3D schematic representations of protein structure

Alternative Views & Representations A: schematic/ribbon B: molecular/ball & stick C: view from top D: space filling model