Biochemistry of Molcules

compounds which have the same molecular formula but different molecular structures structural + sterioisomers

same compoment atoms but arranged differently can be; chain, position and functional group isomers

same molecular formula but chain of carbon atoms present is arranged differently between isomers usually occurs in the presence of 1 or more side chain eg saturated fatty acid

same carbon skeleton and fucntional groups location of functional groups on carbon skeleton differs could be bonding structure or a group of atoms

different functional groups present between molecules with same molecular formula changes in functional group will change function of the compound

compounds that differ in spatial configuration have same formation of bonds but 3D structure is different can be; geometric or optical

compounds that have same number/type of atoms and fundamental layout different spatial arrangement of atoms or groups on either side of fixed chemical bond (rotation can occur) eg across C C bonds- double bonds fixed, free rotation around single can be in cis or trans formation cis= r groups on same side of C C bond (below) trans= r groups on opposite sides of C C bond

compounds with same chemical structure that are non superimposable mirror images of eachother 4 unique r groups bonded to carbon atom chiral compounds chiral- different groups on either side of plane achiral- same groups on either side of plane two compounds that are optical isomers of eachother are called enantiomers this changes chemical properties

functions in cellular energy production and building nucleic acids sugars in their smallest form glucose, fructose, galactose

condensation reaction occurs forming a glycosidic bond between monosaccharides loss of water

oligosaccharides- chain of 3-10 monosaccharides polysaccharides are long chains of monosaccharides

group of chemicals- mostly insoluble in water can be liquid (oil) or solid (wax) form essential nutrient for biological function used in energy production at low to medium intensity exercise (fat oxidation) main constitutional of cell walls and deposits of fats around organs for protection

simplest forms made up as fatty acid compounds organic chains with carboxyl functional groups

glycerol backbone and three bonded fatty acids (triacylglycerols) fatty acids bond to glycerol by a condensation reaction (carboxyl to hydroxyl group) make up main constituent of body fat saturated= c-c or unsaturated- c=c c=c can be cis or trans

20 genetically encoded in dna proteinogenic amino acids proteins made up of long chain a amino acids joined by peptide bonds (N terminus to C terminus) amine group- NH2 side chain- R group carboxyl group- COOH

formed via condensation reaction between carboxyl and amine groups can include two amino acids or more proteins are complex polypeptide structures

amino acids sequence written from N to C terminus

local structural features- commonly observed motifs forming regular repeats alpha helix, beta sheets formed by interactions between neighbouring molecules (hydrogen bonds)

each C=o forms hydorgen bond with amine H (4) between carboxyl and amine groups helix turns right handed (clockwise)

angular conformation of peptide chain causes zig zag shape backbone can form hydrogen bonds between each segment can be antiparallel or parallel sidechains project alternately above and below the sheet

overall protein conformation caused by side chain interactions- folding of poly chain into 3d shapes many a helix and b sheets twisted around eachother 3d shape is influenced by intermolecular forces and hydrophobicity ionic bonds, disulphide bridges, hydrogen bonds

made up a number of subunits two or more chains structure refers to the way in which four subunits interact with eachother arrangement due to intermolecular forces

combination of many interactions (covalent and non covalent) responsible for different levels of structure electrostatic, π- π stacking, hydrophobic , disulphide bridges, hydrogen bonding