PROTEINS

1 EJC H2 Biology T1W9 Proteins Biomolecules of Life (Part 2) - Proteins 1. Overview of Topic Compounds that contain carbon atoms are said to be organic and the branch of chemistry that specializes in the study of carbon compounds is called organic chemistry. This set of lecture notes covers the topic of Proteins. Nucleic acids will be covered in the Core Idea 2: Genetics and Inheritance. These four major classes of biomolecules function as molecular building blocks for macromolecules to be assembled. Macromolecules are often called polymers because each polymer molecule is a long molecule consisting of many similar or identical building blocks linked by covalent bonds. Each repeating unit of a smaller molecule is called a monomer. 2. Learning Outcomes a. Describe the structure and properties of the following monomers: i. amino acids (in proteins) (knowledge of chemical formulae of specific R - groups of different amino acids is not required). b. Describe the formation and breakage of the following bonds: i. peptide bond c. Explain primary structure, secondary structure, tertiary structure and quaternary structure of proteins, and describe the types of bonds that hold the molecule in shape (hydrogen, ionic, and disulfide bonds, and hydrophobic interactions). d. Explain the effects of temperature and pH on protein structure. e. Describe the molecular structure of the following proteins and explain how the structure of each protein relates to the function it plays: i. haemoglobin (transport) ii. collagen (structural) iii. G-protein linked receptor (signalling) – to be covered in cell signalling (knowledge of details of the number of amino acids and types of secondary structures present is not required.)

2 EJC H2 Biology T1W9 Proteins 3. References Campbell, N.A. and Reece, J.B. (2011), Biology (9th edition), Pearson Benjamin- Cummings, San Francisco Brooker, R.J., Widmaier, E.P., Graham, L. and Stiling, P. (2008), Biology, Mc- Graw-Hill, New York

3 EJC H2 Biology T1W9 Proteins Contents 1. Overview of Topic ................................ ................................ ....................... 1 2. Learning Outcomes ................................ ................................ ..................... 1 3. References ................................ ................................ ................................ . 2 4. Introduction ................................ ................................ ................................ . 4 5. Components of proteins ................................ ................................ .............. 6 6. Structure of amino acids ................................ ................................ ............. 6 7. The classification of amino acids ................................ ................................ . 7 8. Properties of amino acids ................................ ................................ ..........