Proteins and Amino Acids Flashcards
What are the components of an amino acid?
Amino group
Acidic carboxyl group
Hydrogen atom
R group
Name the essential amino acids.
M - methionine
V - valine
W - tryptophan
F - phenylalanine
I - isoleucine
K - lysine
T - threonine
L -leucine
H - histidine
How is the amino group found in amino acids?
Protonated to NH3+
How is the carboxyl group found at physiological pH?
COO-
What is the carbon next to the carboxyl group called?
Alpha carbon
Chiral centre
How many stereoisomers can a molecule with a single chiral carbon have?
2
What is an enatiomer?
Stereoisomers which are mirror images of each other but cannot be superimposed on each other
What form are human amino acids found in?
L form
Where are D form amino acids found?
Peptides of bacterial cell walls and antibiotics
What amino acids have non-polar, aliphatic R groups?
G - Glycine
L - Leucine
I - Isoleucine
V - Valine
M - Methionine
A - Alanine
P - Proline
Which amino acid is actually an imino acid?
Proline
What does proline’s structure mean for its funciton?
Rigid structure means that it reduces flexibility of polypeptides that contain it e.g. collagen
What amino acids have aromatic R groups?
W - tryptophan
F - phenylalanine
Y - Tyrosine
Which amino acids with aromatic R groups are more polar?
Tyrosine - due to its OH group
Tryptophan - due to its N indole ring
What unique ability do tyrosine and tryptophan have?
Can absorb UV light
