proteins Flashcards
proteins:
what’s the polymers?
what’s the monomers?
monomers- amino acids
polymers- proteins
what are the chemical elements in proteins.
C H O N (S)
what’s a dipeptide?
what’s a polypeptide?
dipeptide- 2 amino acids joined together
polypeptide- 2+ amino acids joined together
what are proteins made up of?
one or more polypeptides
what’s the general structure of an amino acid
R group, carbon, hydrogen, amino group, carboxyl group
textbook pg 59
what bond joins amino acids?
peptide bond
what reaction joins amino acids?
synthesis:
condensation
OH+H forms a molecule of water - carboxyl and amine interact
how are peptide bonds broken?
hydrolysis
adding molecule of water
assisted by protease (enzyme)
what are the levels of protein structure?
primary
secondary
tertiary
quaternary
what is the primary structure?
- sequence of amino acids in the poly peptide chain
what is in the secondary structure?
- the hydrogen bonds forming between nearby amino acids in the chain
- making it coil into an alpha helix or a beat pleated sheet
what’s in the tertiary structure?
-the further folding or coiling of the amino acids -> from the secondary structure bring R groups of different amino acids closer together so more interactions and bonds form
-if it’s a single polypeptide chain this is their final 3D structure
what’s in the quaternary structure?
-how multiple different polypeptide chains (subunits) are assembled together
eg insulin is made of 2 bonded together poly peptide chains
eg haemoglobin is made of 4 bonded together polypeptide chains
-proteins with more than 1 polypeptide chain this is the proteins final 3D structure
what type of bonding is holding the primary structure of the protein together?
peptide bonds between amino acids
what type of bonding is holding the secondary structure of the protein together?
hydrogen bonds between nearby amino acids in the chain
what type of bonding is holding the tertiary structure of the protein together(describe)? [4]
• ionic bonds- between oppositely charged R groups
• disulfide bonds/bridges- covalent, between R groups containing sulfur atoms
• hydrogen bonds- between same slightly charged atoms in R groups on polypeptide chain
•hydrophobic+hydrophilic interactions-hydrophobic R groups interact and clump together so hydrophilic R groups are pushed to the outside. affects folds in final structure
what type of bonding is holding the quaternary structure of the protein together?
determined by tertiary so all bonds could influence
order the bonds weakeast to strongest in the tertiary structure.
weakest: hydrophobic/philic interactions
hydrogen
ionic
strongest: disulfide
what are the named types of protein? [3]
- globular -> conjugated
- fibrous
what’s the structure of a globular protein?
hydrophilic R groups on amino acids pushed to outside of protein, caused by the folds from hydrophobic and hydrophilic interactions in tertiary structure
what’s the example of a globular protein?
insulin
what’s the example of a globular protein?
insulin
what’s insulin?
hormone released by pancreas, into bloodstream
helps regulate blood glucose concentration
what’s the structure of insulin?
2 poly peptide chains, held together by disulfide bond
