Flashcards in Lecture 5 - Protein Strucutre Deck (29):
Are structural proteins usually drug targets?
Which structural protein has been useful in drug design?
What are the three main drug target proteins?
Receptors, enzymes and transporters
What do transport proteins do (3)?
-Transport chemical building blocks (polar) across the cell membrane
-Transport neurotransmitters back into the neuron
What can go wrong with receptors?
-Over-activation of the cell due to too much messenger
-Under-activation of the cell due to tell little messenger
How do we fix over-activation and under-activation?
What are the three families of receptors?
What is signal-transduction
The chain of events that involve secondary messengers, proteins and enzymes
What is the difference between the 3 types of protein drug targets?
1) Enzymes - there is a chemical transformation of the LMW compound
2) Receptors - there is a message and the LMW compound leaves unchanged
3) The LMW is moved into the cell unchanged after binding
What do all amino acids have? (4)
Carboxylic acid groups (Co2H)
Amino group (NH2)
Functional group (R)
Central C-H motif
What is special about the structure of proline
The side chain is bonded to both the amino and carboxylate groups
Where is proline normally found in the protein?
Why is proline also termed an imino acid
It has a 2° amino group instead of a 1° amino group
What are the two S-containing amino acids
Do charged amino acid residues stabilise protein conformations?
What are two non-standard amino acids?
Selenocysteine and pyrrolysine
What is a peptide bond
CO-NH with water spat out
Is the carbonyl atom usually cis or trans to the amino acid H atom
Does the amide bond undergo rotation?
No it has some double bond character
What is primary protein structure?
The order in which amino acids are linked together
What is secondary protein structure?
Ordered regions within the protein, from specific hydrogen-bonding patterns
What is the tertiary protein structure?
The spatial arrangements of all atoms (including side chains and formation of disulfide bonds)
What is quaternary protein structure
The arrangement of two or more subunits
What are some examples of secondary structure
alpha helix, parallel beta sheet, anti-parallel beta sheet
Parallel beta sheets have what two groups on the same side?
What is a key contributor to tertiary structure?
Van der waals
What amino acid residues will be located at the surface of proteins?
What is the result of the polar amino acid residues located at the surface?
They are less able to participate in the maintenance of the tertiary structure