Protein Basics Protein function Protein structure Protein Basics Notes Protein Basics Protein function Protein structure Primary Amino acids Linkage Secondary Tertiary Quaternary Effect of DNA Mutation

Protein Function in Cell Enzymes Catalyze biological reactions Structural role Cell wall Cell membrane Cytoplasm

DNA  RNA  Protein  Trait A. Bio-molecules are the basis of traits DNA  RNA  Protein  Trait • Traits represent organisms': - Structure - Function • Proteins determine structure and function • DNA codes for proteins that convey traits

Protein Basics Notes Frank Lloyd Wright

Levels of Protein Structure Protein Basics Notes Levels of Protein Structure The Shape it takes depends on the order of the Amino Acids

From our last set of notes: Translation Second stage of protein production mRNA is on a ribosome

Primary structure = order of amino acids in the protein chain Protein Basics Notes Primary structure = order of amino acids in the protein chain

Membrane proteins have adapted to hydrophobic environments Protein Basics Notes Membrane proteins have adapted to hydrophobic environments

Secondary structure = local folding of residues into regular patterns Protein Basics Notes Secondary structure = local folding of residues into regular patterns

Tertiary structure = global folding of a protein chain Protein Basics Notes Tertiary structure = global folding of a protein chain

Tertiary structures are quite varied Protein Basics Notes Tertiary structures are quite varied

Quaternary structure = Higher-order assembly of proteins Protein Basics Notes Quaternary structure = Higher-order assembly of proteins

Example of quaternary structure - Sir1/Orc1 heterodimer Protein Basics Notes Example of quaternary structure - Sir1/Orc1 heterodimer Example is Sir1/Orc1 complex solved at UW: Hou, Bernstein, Fox, and Keck (2005) Proc. Natl. Acad. Sci. 102, 8489-94.

Ex: Quaternary structures – Protein Basics Notes Ex: Quaternary structures – You don’t need to memorize these types Tetramer Hexamer Filament SSB DNA helicase Recombinase Allows coordinated Allows coordinated DNA binding Allows complete DNA binding and ATP hydrolysis coverage of an extended molecule

Protein: The Machinery of Life NH2-Val-His-Leu-Thr-Pro-Glu-Glu- Lys-Ser-Ala-Val-Thr-Ala-Leu-Trp- Gly-Lys-Val-Asn-Val-Asp-Glu-Val- Gly-Gly-Glu-….. “Life is the mode of existence of proteins, and this mode of existence essentially consists in the constant self-renewal of the chemical constituents of these substances.” Friedrich Engles, 1878

DNA Mutation Function Students know how mutations in the DNA sequence of a gene may or may not affect the expression of the gene or the sequence of amino acids in an encoded protein.