Types of macromolecules Carbohydrates Lipids Proteins Nucleic acids Proteins Chief building blocks of life 1000s of proteins Lots of different functions, but all built the same way & from the same raw material in all organisms Made of 20 amino acids, the protein alphabet Store energy in bonds which can be used to fuel living processes The building blocks of proteins Unique combinations of amino acids result in proteins with unique structure & function Made of a central C atom with a carboxyl group, amino group & a side chain the side chain determines the characteristics of each amino acid Amino acids = side chain 1
Expanded amino acid structures Making proteins Proteins formed by linking individual amino acids together with a peptide bond amino group of one amino acid binds to the carboxyl group of another 2 linked amino acids = dipeptide Several linked together = polypeptide chain Protein structure and function Most enzymes and other proteins are globular in shape (like popcorn) Structural proteins typically are fibrous Shape is very specific to job If proteins lose their shape they cannot function properly, called denaturation caused by changes in ph or excessive heat ex. cooking eggs; heat breaks H-bonds, proteins unfold & lose shape 2
Four levels of protein structure Primary The unique sequence of amino acids Secondary The twists & folds formed by H-bonding between amino acids in the peptide chain Four levels of protein structure Tertiary The complex folding in the polypeptide chain resulting from interactions between side chains Quaternary Formed when 2 or more polypeptide chains bind together Enzymes Proteins that initiate & speed up chemical reactions in living organisms Can be used over & over Shape is critical, just like all other proteins substrate-specific even slightly altered enzymes can become non-functioning non-functioning enzymes are responsible for a large # of diseases & physiological problems 3
Types of macromolecules Carbohydrates Lipids Proteins Nucleic acids Nucleic acids Macromolecules that store information Two types DNA & RNA both play central roles the production of proteins & determining the inherited traits of individuals Made up of nucleotides a sugar a phosphate group a nitrogenous base Nucleic acids continued Both DNA & RNA have a sugar-phosphate backbone attached to each sugar is the nitrogenous base cytosine guanine adenine thymine (DNA only) uracil (RNA only) Different sequences of bases makes different proteins 4
DNA = Deoxyribonucleic acid Holds genetic information to build a whole organism (!!!) 2 strands, each wrapping around each other, forming a double helix sugar-phosphate backbone on the outsides and nitrogenous bases facing inward base bind together with hydrogen bonding bases pair up with each other in 2 combinations A with T C with G RNA = ribonucleic acid The universal translator Directs protein production Differs from DNA sugar of backbone has an extra O atom single stranded; bases don t bind with anything else uracil instead of thymine (U instead of T) Macromolecules summary Carbohydrates: energy & structure monosaccharides polysaccharides Lipids: hydrophobic triglycerides sterols phospholipids waxes Proteins: building blocks of life structure & function intimately related Nucleic acids: store information DNA RNA 5