Biomolecules: Nucleic Acids and Proteins

Nucleic Acids: DNA and RNA Carry and transmit detailed instructions for building every human cell and for every cell of every living organism

Nucleic Acids Polymer made of monomers – nucleotides Contain – Carbon, Hydrogen, Oxygen, Nitrogen and Phosphorus Store and Transmit all genetic information 2 Types: Deoxyribonucleic acid - DNA Ribonucleic acid – RNA

Nucleic Acid Monomers - nucleotides G T U

Proteins: Do All The Work Large and complex Polymers, made up of long chains of amino acids (monomers) Instructions for building Proteins are "written" in DNA They have diverse biological roles/ jobs

Protein Jobs Structure and support: main components of our tissues – muscle, skin, hair, ligaments, etc. Communication & signaling – they can be signals (some hormones are proteins) or the receivers of signals (receptors) Defense: All antibodies are proteins Regulation: Regulate all processes in the cell Catalysis: Enzyme are catalysts, regulation all chemical reactions in cells

Amino Acids – the monomers of Proteins amino group carboxylic acid group Carboxyl Group R group All amino acids have the same general structure: the only difference between each one is the nature of the R group. So the R group defines an amino acid. It represents a side chain from the central “alpha” carbon atom, and can be anything from a simple hydrogen atom to a more complex ring structure.

Amino Acid – Polar or Not?

There are 20 Amino acids

Building Proteins from Amino Acids Dehydration synthesis: Carboxyl Group of 1st Amino Acid is linked to the Amino Group of the 2nd Amino Acid and 1 molecule of water is removed. The bond formed is called a Peptide bond/Peptide linkage. Dipeptide – 2 Amino Acids linked repeat steps to produce Polypeptide – many Amino Acids linked

Polypeptides When more amino acids are added to a dipeptide, a polypeptide chain is formed. A protein consists of one or more polypeptide chains folded into a highly specific 3D shape. Each Protein has a unique 3D Shape which is determined by the order in which the Amino Acids are arranged

Protein Structure There are up to four levels of structure in a protein: primary - the order, sequence of amino acids secondary - hydrogen bonds cause simple folding of the chain tertiary – 3D folding - shape of protein quaternary – when 2 or more polypeptide chains interact

Structure of hemoglobin

How is the 3D Shape held together? hydrogen bonds: involved in all levels of structure. hydrophobic interactions: between non-polar sections of the protein. disulfide bonds: one of the strongest and most important type of bond in proteins. Occur between two cysteine amino acids.

How can we destroy the shape of a Protein? hydrogen bonds: involved in all levels of structure. hydrophobic interactions: between non-polar sections of the protein. disulfide bonds: one of the strongest and most important type of bond in proteins. Occur between two cysteine amino acids.