Chapter 4 Flashcards
How many common R groups are there?
20
What makes up an alpha amino acid?
Central Carbon (alpha)
Amine
Carboxylic Acid
R group
Hydrogen
Is the amine on an amino acid strong or weak?
Week base
Is the carboxylic acid on an amino acid strong or weak?
Weak acid
What is on the N-terminus of an amino acid?
Amine
What is on the C-terminus of an amino acid?
Carboxylic acid
What does an amino acid look like at pH 7.4?
Protonated (+) Amine
Deprotonated (-) Carboxylic acid
What type of acids are amino acids?
Weak polyprotic acid
What is the pKa of the carboxylic acid group on an amino acid?
2
What is the pKa of the amino group on an amino acid?
9
What are the 3 and 1-letter codes for Glycine?
Gly
G
What are the 3 and 1-letter codes for Alanine?
Ala
A
What are the 3 and 1-letter codes for Valine?
Val
V
What are the 3 and 1-letter codes for Leucine?
Leu
L
What are the 3 and 1-letter codes for Isoleucine?
Ile
I
What are the 3 and 1-letter codes for Methionine?
Met
M
What are the 3 and 1-letter codes for Proline?
Pro
P
What are the 3 and 1-letter codes for Phenylalanine?
Phe
F
What are the 3 and 1-letter codes for Tryptophan?
Trp
W
Describe the R group of glycine:
H
Describe the R group of Alanine:
CH3
Describe the R group of Valine:
CH(CH3)2
Describe the R group of Isoleucine:
CH(CH2CH3)CH3
Beta carbon with a methyl, ethyl, and hydrogen on it
Describe the R group of Methionine:
CH2-CH2-S-CH3
Describe the R group of Proline:
C(a)-CH2-CH2-CH2-NH2+
Three carbon chain that attaches to the amino group in the backbone
Describe the R group of Phenylalanine:
CH2-C6H6
One carbon into a benzene ring
Describe the R group of Tryptophan:
CH2-C4H1NH-C4
One carbon into a 5-member ring with an N, and off of that ring a benzene
What are the 3 and 1-letter codes for Serine?
Ser
S
What are the 3 and 1-letter codes for Threonine?
Thr
T
What are the 3 and 1-letter codes for Asparagine?
Asn
N
What are the 3 and 1-letter codes for Glutamine?
Gln
Q
What are the 3 and 1-letter codes for Tyrosine?
Tyr
Y
What are the 3 and 1-letter codes for Cysteine?
Cys
C
Describe the R group of Serine:
CH2-OH
Describe the R group of Threonine:
CH(CH3)OH
Beta carbon with a alcohol, methyl, and hydrogen
Describe the R group of Asparagine:
CH2-CO(NH2)
CH2 with a C that is double bonded to an oxygen and has an amino group
Describe the R group of Glutamine:
CH2-CH2-CO(NH2)
Two CH2s and then a C that is double bonded to an oxygen and has an amino group
(Asparagine with an extra CH2)
Describe the R group of Tyrosine:
CH2-Ph
CH2 attached to a benzene ring that has an OH in the para position
Describe the R group of Cysteine:
CH2-SH
What are the 3 and 1-letter codes for Lysine?
Lys
K
What are the 3 and 1-letter codes for Arginine?
Arg
R
What are the 3 and 1-letter codes for Histadine?
His
H
What are the 3 and 1-letter codes for Aspartic Acid?
Asp
D
What are the 3 and 1-letter codes for Glutamic Acid?
Glu
E
Describe the R group of Lysine:
-CH2-CH2-CH2-CH2-NH3+
Describe the R group of Arginine:
-CH2-CH2-CH2-NH-C(NH2)NH2+
3 Carbon chain with a NH attached to a Carbon that is boned to an amino group and double bonded to another amino group that has a positive charge
Describe the R group of Histadine:
CH2-(5member ring with 2 nitrogens)
A CH2 attached to a carbon that is in a 5 member ring with a two two NH; One of the NH groups are in a double bond and thus have a positive charge
Describe the R group of Aspartic Acid?
CH2-COO-
Describe the R group of Glutamic Acid:
CH2-CH2-COO-
What is the isoelectric point for amino acids?
The pH at which the net charge on the amino acid or protein is neutral
What is the formula for pI?
pI = 1/2 (pKa1 + pKa2)
Why is there no racemic mixtures in biochemistry?
Enzymes
What is the stereochemistry of most amino acids? Which one is different?
Chiral
Glycine - achiral
What type of amino acid predominates the stereochemistry?
L-amino acids
When do we use the R/S stereochemistry naming instead of L/D?
When more than one stereocenter is present
What is the difference between an (L) and (D) amino acid?
L: NH3+ on left
D: NH3+ on right
Are L-amino acids S or R? What is the exception?
All L-amino acids are (S)-amino acids, except for Cys
What is the difference between essential and nonessential amino acids?
Essential - must come from diet
Nonessential - body produces
How many amino acids are essential?
10
What is the function of the GABA amino acid?
Neurotransmitter
What is the function of Histamine?
Inflammation/Allergic Reaction
What is the function of Dopamine?
Neurotransmitter
What is the function of Thyroxine amino acid?
Thyroid hormone