Amino Acids Flashcards
What 2 functional groups are in Amino Acids?
Amino group and Carboxyl group
What makes each amino acid different?
R groups: side chains
What is a peptide bond?
1 amino acid’s carboxyl group bonds with another’s amino group
What do each of these mean: Dipeptide, Oligopeptide, and polypeptide.
Dipeptide: 2 monomers joined
Oligopeptide: many monomers joined
Polypeptide: more than 50 monomers joined (can make proteins)
Name the non-polar amino acids:
Aliphatic side chains: Glycine, Alanine, Valine, Leucine, Isoleucine
Methionine
Cysteine (can form disulphide bonds)
Aromatic: Phenylalanine, Tryptophan
Proline (link to alpha-amino group)
What bonds can non-polar amino acids form?
No hydrogen bonds (hydrophobic)
Name the polar amino acids:
Alcohols: Serine, Threonine, Tyrosine
Asparagine, Glutamine (amides of aspartate and glutamate)
What minds do polar amino acids make?
Hydrogen bonds not ionic
Name the charged amino acids:
Acidic: Aspartame, Glutamate
Basic: Lysine, Histidine, Arginine
What bonds can be made in charged amino acids?
Hydrogen bonds and ionic bonds
What are the ends of the proteins?
N-terminus (amino group) and C-terminus (carboxyl group)
What bonds in a polypeptide chain are flexible and which is rigid?
Single bonds are flexible and double bods are rigid but the polypeptide chain itself is flexible
Describe the secondary structure of an amino acid:
Interactions within polypeptide backbone
What types of secondary structures are there?
Alpha helix: hydrogen bonds every 3 residues; form of a helix
Beta Pleated sheets: 2 strands folded back and forth forming hydrogen bonds across
Random coil: joins 2 structures but has no structure itself
What are tertiary structures?
Interactions of side chains (R-groups)
What types of bonds are there in the tertiary structure of the amino acids?
Hydrogen bonds, ionic bonds, disulphide bonds and hydrophobic interactions between R-groups
Describe the Quaternary structure of an amino acid:
More than 1 polypeptide chain; interactions between 2 or more subunits of a protein
What is a native protein?
Correctly folded protein and has bonds
What do you called an unfolded protein? How are the bonds within broken?
Denatured proteins. Bonds are broken by putting in energy
What is a way to analyze proteins?
Polyacrylamide gel
Describe a fatty acid binding protein
Hydrophobic tail and a polar head with a negative charge
How do we know the structure? Describe the steps.
X-ray crystallography
Single crystal gives diffraction pattern which gives the electron density map and then finally you can determine the protein model
