1A-Proteins Flashcards
what monomer are proteins made of
amino acids
what are amino acids general structure
a carboxyl group, amino group and a carbon containing R group (variable side group)
refer to pg 31
how are amino acids linked together
by condensation reaction
what is the bond between amino acids called
peptide bond
refer to pg 31
what is the primary structure
sequence of amino acids in the polypeptide chains
what is a secondary structure
polypeptide chain doesn’t remain flat and straight. hydrogen bonds form between amino acids in the chain making it coil into an alpha helix or a beta pleated sheet
what is the tertiary structure
its coiled and folded further. more bonds form between different parts of the polypeptide chain (hydrogen and ionic bonds)
Disulfide bridges form whenever two molecules of amino acids cysteine bonds to the sulfur atom in the other. for proteins made from a single polypeptide chain the tertiary structure forms their final 3D structure
what is a quaternary structure
the way these polypeptide chains are assembled together
for proteins made from more than one polypeptide chain the quaternary structure is the protien’s final 3D structure
what is the biuret test for proteins
add a few drops of sodium hydroxide solution to make the solution alkaline
then add copper(II) sulfate solution
if present then solution turns purple otherwise it stays blue
why are enzymes highly specific?
because of their tertiary structure
what is the activation energy
certain amount of energy supplied to chemical before reaction starts
what do enzymes do
they lower the activation energy to speed up the reaction
what is an enzyme-substrate complex
when an substrate fits into the enzyme’s active site
how does an enzyme-substrate complex lower the activation eneryg
because two substrate molecules that need to be joined will be held close together by the enzyme reducing repulsion between molecules so easier to bond
fitting in the active site puts a strain on the bonds in the substrate o substrate molecules will break more easily
what is the lock and key theory
the substrate and active site have a complementary shape
what is the induced fit model
where the substrate slightly changes the shape of the active site to fit even better.
what are enzyme properties related to
their tertiary structure
why are enzymes specific
becuause only complementary substrate will fit into the active site
what determines the active site’s shape and how why does it mean a different active site
the tertiary structure each enzymes has different tertiary structure so different active site
what would it mean if the tertiary structure of a protein is altered
shape of active site changes meaning substrate won’t fit into active site and enzyme-substrate complex won’t be made and enzyme will no longer be able to carry out its function.
ways of altering the tertiary strucutre of an enzyme
temperature and ph
what happens if a mutation occurs
primary structure of protein determined by gene if mutation occurs it could change tertiary structure of enzyme produced
