Amino Acids and Protein Structure Flashcards
what amino acids contain a hydroxyl group that can be replaced by a phosphoryl group
serine, threonine, tyrosine
what is glycolysation
addition of chains of sugars
what amino acids can undergo glycolysation
- Serine and threonine (O linked glycolysation)
2. Asparagine (N linked glycolisation)
what amino acid can a hydrocarbon chain be added to
cysteine because of its reactive sulfhydryl group
what amino acids have acidic side chains
glutamic acid and aspartic acid
what will a titration curve of an acidic AA chain look like
THREE buffering zones
what are the basic AAs
histidine, lysine, arginine
what bonds join proteins
peptide bonds between amino and carboxyl group
primary structure
linear order of AA starting at amino terminus
alpha helix produced by
hydrogen bonds forming between atoms in peptide bonds of a single linear chain
beta sheet produced by
hydrogen bonds forming between atoms in peptide bonds of the same or different linear chains
SAME: parallel
DIFFERENT: anti parallel
tertiary structure
overall 3D conformation determined by AA sequence. Peptide bond backbone and amino side chains determine this. H BONDS, IONIC BONDS, VAN DER WAALS
how do you get covalent interactions in AA side chains
two cysteines undergo formation of a covalent disulfide bond to make cysteine residue
domain
particular region of a protein with specific structure and function
quarternary structure
arrangement of protein subunits in complex that contains more than one polypeptide
what about proline limits the conformation
the ring (which is NOT aromatic)
fatty acetylation
attach to a sulfur group
4 helix bundle
hydrophobic core stabilized by ionic interactions
tim barrel
8 alpha helices and 8 parallel b strands
non globular proteins
- coiled coil (keratin)
- instrinsically disordered - few hydrophobic which is what drives folding - not stable at physiological conditions but very important regulators
