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The 20 amino acids. A Ala Alanine. Small Hydrophobic Helix: ++ Strand: – Turn: – – Mutate to Ala if you have to mutate but have no clue to which residue. C Cys Cysteine. Small Hydrophobic Sulfur containing Helix: – Strand: + Turn: + The SH- group is very reactive :
E N D
A Ala Alanine • Small • Hydrophobic • Helix: ++ • Strand: – • Turn: – – • Mutate to Ala if you have to mutate but have no clue to which residue
C Cys Cysteine • Small • Hydrophobic • Sulfurcontaining • Helix: – • Strand: + • Turn: + • The SH-group is veryreactive: • Can make Cys-Cysbridges • Can bind metal ions (especially Zn and Cu)
D Asp Aspartate • Intermediately large • Hydrophilic • Negativelycharged • Helix: - (but ++ at N-terminus) • Strands: – – • Turn: ++ • Often in active sites • Can bind ions (mainly calcium)
E Glu Glutamate • Large • Hydrophilic • Negatively charged • Helix: ++ • Strand: 0 • Turn: –
F Phe Phenylalanine • Large • Hydrophobic • Aromatic • Helix: + • Strand: ++ • Turn: – –
G Gly Glycine • Smallest residue • No side chain • Hydrophobicity undetermined • Very flexible • Star of the turns • Helix: – – • Strand: –- • Turn: ++
H His Histidine • Large • Hydrophilic • Charge (depends on the environment): • Positive • Neutral • Negative • No secondarystructurepreference • Often in active sites • Can bind metal ions (mainly Zn, Ni, Cu)
I Ile Isoleucine • Intermediately large • Hydrophobic • Helix: + • Strand: ++ • Turn: – –
K Lys Lysine • Large • Hydrophilic • Positively charged • Helix: ++ • Strand: 0 • Turn: 0 • Long, flexible side chain
L Leu Leucine • Intermediately large • Hydrophobic • Helix: ++ • Strand: + • Turn: – –
M Met Methionine • Large • Hydrophobic • Sulfurcontaining • Helix: ++ • Strand: + • Turn: – – • Non-reactivesulfurwhichcan bind metal ions • Often the first residue of the sequenceandtherefore at the surface (forced marriage)
N Asn Asparagine • Intermediately large • Hydrophilic • Helix: – – • Strand: - • Turn: ++ • Can bind ions (Ca) but not as well as its isosteric partner Asp
P Pro Proline • Small • Hydrophobic • Helix: – – (except at the first position) • Strand: – – • Turn: ++ • Imino acid • No backbone proton • Pre-bend for turns (forced marriage)
Q Gln Glutamine • Large • Hydrophilic • Helix: + • Strand: 0 • Turn: 0 • Isosteric with Glu
R Arg Arginine • Large • Hydrophilic • Positively charged • No secondary structure preference • Contains a rigid guanidinium group
S Ser Serine • Small • Intermediatehydrophobicity • Alcoholic • Helix: – • Strand: – • Turn: ++ • Often in active sites (withAspand His) • Can bind calcium
T Thr Threonine • Small • Intermediate hydrophobicity • Alcoholic • Helix: 0 • Strand: ++ • Turn: 0 • Can bind calcium
V Val Valine • Small • Hydrophobic • Helix: 0 • Strand: ++ • Turn: – – • Isosteric with Thr
W Trp Tryptophan • Largest residue • Hydrophobic • Aromatic • Helix: 0 • Strand: ++ • Turn: 0 • Most conserved residue
Y Tyr Tyrosine • Large • Intermediate hydrophobicity • Aromatic • Alcoholic • Helix: – • Strand: ++ • Turn: 0