Lecture 5 Flashcards
What are the positive side chains
Lysine, histidine , arginine
What is the Pi
Isoelectric point-pH at which molecule or surface has no net charge
What aa’s are in the R aromatic group
Phenylalanine, tyrosine and tryptophan
What is a residue
The part of the amino acid that remains after a peptide bond is formed
What is the typical pKa of a terminal a-carboxyl group
3.1
What is the typical pKa of an aspartic or glutamic acid side chain
4.1
What is the typical pKa of a histidine sidechain
6
What is the typical pKa of a terminal a-amino group
8
What is the typical pKa of a cysteine side chain
8.3
What is the typical pKa of a tyrosine side chain
10.9
What is the typical pKa of a lysine side chain
10.8
What is the typical pKa of an arginine side chain
12.5
What is an amino acid with 2 carboxylic groups
Asp
When the pI is less than the pH what charge will there be
A positive net charge
Why is a peptide bond planar
Because it has partial double bond character , preventing rotation
What does dihydrofolate reductase (DHFR) do
I converts dihydrofolate to tetrahydrofolate (NADPH is the coenzyme)
Why is dihydrofolate reductase important
Important in one carbon metabolism eg synthesis of nucleus acids. Also important I’m cancer chemotherapies.
Name 2 important chemotherapy drugs
Methotrexate and trimethoporin
2 examples of chemical denaturants for unfolding of Ribonuclease a
Urea and guanidium chloride
