pI = (pk1 + pk2)/2, the pH where the molecule has a net charge of 0
green fluorescent protein (GFP)
blue
O
O2
Phe-Ser-Tyr-Gly-Val-Gln
69
64
N
HO
H
O
N
N
Phe
green
O
Gln
Val
H
Ninhydrin Test
Ion Exchange Chromatography
size exclusion chromatography
Protein separation
ultrafiltration
ultracentrifugation
least soluble at their IP
Step 1. Separation of Polypeptide Chains
dissociated by exposure to pH extremes, 8 M urea,
6 M guanidinium hydrochloride,
or high salt cencentrations
Cleavage of disulfide bridges
Edman degradation
phenylisothiocyanate
50 cycles of reaction can be accomplished on 50 pmol (about 0.1 mg
)
Carboxypeptidases cleave amino acid residues from the C-termini
Cyanogen bromide
Fmoc solid phase peptide synthesis: A Practical Approach
Edited by
Weng C. Chan and Peter D. White
OXFORD UNIVERSITYPRESS
2000