Transcript Protein
PROTEINS June 2, 2016 Functions 1. 2. Building Blocks a. Structural components of many cells Antibodies a. Involved in defending the body against foreign invaders Functions (cont.) 3. Enzymes a. Catalyze chemical reactions b. Examples: Amylase and Lactase c. They can become Denatured 1. When they lose their function and shape in extreme conditions 2. Examples: milk souring, cooking eggs Functions 4. 5. Signaling a. Cells signal one another 1. Example: Muscle contraction Transporters a. Bind to molecules and carry them to other cells Structure 1. Made up of monomer units called… Amino Acids a. Bonded together through the process of….. b. Dehydration Synthesis Break polymers up through process of… Hydrolysis A D B C Macromolecule Units Review Monomer Smallest unit of macromolecule Polymer Formed when many monomers bond How do you make Macromolecules? Dehydration Synthesis Polymers are formed by removing water from monomers How do you break a macromolecule? Hydrolysis Polymers are broken apart by adding water to break up into monomers Functional Groups Commonly Present 1. Amino Group 2. Carboxyl Group Amino Acid Structure 1. Each Amino Acid has a different combination of elements labeled simply as its “R Group” a. 20 total Amino Acids Nonpolar Polar Acidic Basic 4 Levels of Structure 1. Primary Structure a. A chain of amino acids 1. Bonds between amino acids are covalent or peptide bonds *NOW IT’S CALLED A POLYPEPTIDE (long chain of amino acids) *Each polypeptide differs in the number & arrangement of the amino acids’ R groups Formation of a peptide bond Formation of a peptide bond (cont.) Protein Structure 4 Levels of Structure (cont.) 2. Secondary Structure a. Arrangement of polypeptides into different formations 1. Alpha helix: Coil or corkscrew formation 2. Beta Sheet: Pleats or folds 3. Random Coils Hydrogen bonding present between an H and O b. Hydrogen Bonding: Alpha and Beta 4 Levels of Structure (cont.) 3. Tertiary Structure a. 3-D folding of secondary structures b. Bonding occurring within the protein due to interaction of R groups Types of R group bonds 1. Hydrophobic interactions occur between Nonpolar R groups 2. Ionic Bonds- occur b/w an acid (-) & base (+) 3. Disulfide bonds- occur b/w 2 cysteine R groups 4. Hydrogen bonds- occur b/w Polar R groups in which an N, O, or F will be present (some exceptions) a. At this stage it is a functional protein Bonding in Tertiary Structure 4 Levels of Structure (cont.) 1. Quaternary Structure a. Tertiary proteins bond with each other (2 or more polypeptides bond), so you have a group of proteins bonded together b. Example: Hemoglobin