,1a
Peptide = protein with less than 50 AA joined by amide bond
Peptides have N-terminus on right and C terminus on left. Naming from N terminus to C
terminus.
AA have an amine and CA group attached to alpha C
Alpha C is chiral (only glycine isn't chiral)
L isomer = S stereochemistry
D isomer = R stereochemistry
L AA are mosr common in nature
L and D are enantiomers
Cysteine is an L AA with R chiral centre which is exception to rule due to priority of "S"
Small AA:
● Glycine (Gly, G)
● Alanine (Ala, A)
Nucleophilic AA:
● Serine (Ser, S)
● Threonine (Thr, T)
● Cysteine (Cys, C)
Hydrophobic AA:
● Valine (Val, V)
● Leucine (Leu, L)
● Isoleucine (Ile, I)
● Methionine (Met, M)
● Proline (Pro, P)
Aromatic AA:
● Phenylalanine (Phe, F)
● Tyrosine (Tyr, Y)
● Tryptophan (Trp, W)
,Acidic AA:
● Aspartic acid (Asp, D)
● Glutamic acid (Glu, E)
Amide AA:
● Asparagine (Asn, N)
● Glutamine (Gln, Q)
Basic AA:
● Histidine (His, H)
● Lysine (Lys, K)
● Arginine (Arg, R)
4 structural levels of peptides: primary (sequence of AA), secondary structure (alpha helix
and beta pleated sheets formed from H bonding), tertiary structure (3D structure of alpha
helix and beta pleated sheets coming together), quaternary structure (two or more proteins
interacting)
Aspirin - small molecule which is cheap and oral delivery available
Insulin - larger peptide drug which is given via injection. High cost of production as enzymes
(proteases) can readily chew up peptides
Overtime, more approved peptides on market as better synthesis techntechniques and
change in targets. More complex peptides are also now synthesised
Solid Phase Peptide Synthesis (SPPS)
SPPS peptides are built from C to N terminus
anchor the 1st molecule to resin bead then add next mol to this “stuck”
molecule
,
Peptide = protein with less than 50 AA joined by amide bond
Peptides have N-terminus on right and C terminus on left. Naming from N terminus to C
terminus.
AA have an amine and CA group attached to alpha C
Alpha C is chiral (only glycine isn't chiral)
L isomer = S stereochemistry
D isomer = R stereochemistry
L AA are mosr common in nature
L and D are enantiomers
Cysteine is an L AA with R chiral centre which is exception to rule due to priority of "S"
Small AA:
● Glycine (Gly, G)
● Alanine (Ala, A)
Nucleophilic AA:
● Serine (Ser, S)
● Threonine (Thr, T)
● Cysteine (Cys, C)
Hydrophobic AA:
● Valine (Val, V)
● Leucine (Leu, L)
● Isoleucine (Ile, I)
● Methionine (Met, M)
● Proline (Pro, P)
Aromatic AA:
● Phenylalanine (Phe, F)
● Tyrosine (Tyr, Y)
● Tryptophan (Trp, W)
,Acidic AA:
● Aspartic acid (Asp, D)
● Glutamic acid (Glu, E)
Amide AA:
● Asparagine (Asn, N)
● Glutamine (Gln, Q)
Basic AA:
● Histidine (His, H)
● Lysine (Lys, K)
● Arginine (Arg, R)
4 structural levels of peptides: primary (sequence of AA), secondary structure (alpha helix
and beta pleated sheets formed from H bonding), tertiary structure (3D structure of alpha
helix and beta pleated sheets coming together), quaternary structure (two or more proteins
interacting)
Aspirin - small molecule which is cheap and oral delivery available
Insulin - larger peptide drug which is given via injection. High cost of production as enzymes
(proteases) can readily chew up peptides
Overtime, more approved peptides on market as better synthesis techntechniques and
change in targets. More complex peptides are also now synthesised
Solid Phase Peptide Synthesis (SPPS)
SPPS peptides are built from C to N terminus
anchor the 1st molecule to resin bead then add next mol to this “stuck”
molecule
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