Proteins Mohamed Bingabr, Ph.D. Associate Professor Department of Engineering and Physics University of Central Oklahoma
Proteins Proteins are the working molecules of cells, performing thousands of functions that are essential for the life of the cell and the organism. Protein Functions: Structure components of cells and tissues Channels for transport molecules through biological barriers Elements in communication systems Recognition elements in the defense against infection Chemical catalysts (Enzyme) Muscle Contraction
Proteins Proteins are polymers of about 20 amino acids (the monomer). Glycine
Proteins Productions Proteins are made up of one or more polypeptide chain. Polypeptides are polymers of amino acids.
Proteins Productions The amino group of one amino acid is covalently linked to the carboxyl group of another amino acid. The linear polypeptide chain fold into its correct 3- dimensional shape to carry its function.
Proteins Structures Proteins have 4 levels of structures: PrimarySecondaryTertiaryQuaternary
Proteins Structures Secondary Tertiary Quaternary
Is it possible to manufacture Protein?
Imaging Proteins Structure Nuclear Magnetic Resonance (NMR): spectroscopy used to find the structure of small protein in solution. X-ray crystallography: used to image large proteins.
Protein Diversity and Function Structure Protein: Found in cell cytoskeleton Protein-rich gel: found on gel that surround cells in tissue. Transmembrane protein: form channels to transport ions across cell membrane. Receptors protein: protein span the membrane and have extracellular domain that bind to ligands molecule. Ligand binding transmit a signal into the cell. Enzyme protein: speed up chemical reaction. Immune protein: antibodies
Modification of Protein Protease: enzyme that are specialized in breaking proteins Example: 1) Digestive enzymes 2) Insulin modification Post-translation modification: Protein is activated by clipping or cleaved a segment of amino acids.
Post-translation Modifications of Proteins
HIV
Protease In HIV Medication r.com/hiv-protease- inhibitors-animation- showing-their- mechanism-of-action/
Enzymes Enzyme can speed up the rate of reaction by a million or more times than an uncatalyzed reaction. Enzyme catalyze chemical reaction by lowering the activation energy of a reaction. hill.com/sites/ /student_view0/chapt er2/animation__how_e nzymes_work.html
Enzymes Reaction time will depend on the concentration of the substrates and the affinity of the enzyme.
Homework Due 3/10/2011 Do the following problems in Ch3 of your textbook: 2, 5, 6, 9, 10