. Author manuscript; available in PMC: 2021 Apr 6.

Published in final edited form as: Chem Rev. 2014 Apr 10;114(11):5815–47. doi: 10.1021/cr400401e

Table 5. Common buffer conditions for oxidative folding of conotoxins.

Standard conotoxin folding conditions

0.1M NH₄HCO₃; pH 7.5 - 8.5; r.t.
0.1M NH₄HCO₃ / 30% i-PrOH (or ACN); pH 7.5-8.5; r.t.
0.33M NH₄OAc / 0.5M GnHCl, GSH:GSSG:peptide (100:10:1); pH 7.8; 4°C
30% DMSO / 5% acetic acid / 65% water; r.t.
30% DMSO / 0.1 M KH₂PO₄; pH 6, r.t.

Additional conditions

0.33M NH₄OAc / 0.5M GnHCl; pH 7.8; 4°C
2M (NH₄)₂SO₄ / 0.1M NH₄OAc; pH 7.7; 4°C
2M GnHCl / 50mM NH₄OAc; pH 7.7; 4°C
0.1M NH₄HCO₃; pH 8; 4°C
0.05M - 0.1M NH₄OAc; pH 7.8-8.4; 4°C or r.t.
0.1M NH₄HCO₃ / 30% i-PrOH; pH 8; r.t.
0.1M NH₄HCO₃ / 15% DMSO / 30% TFE; pH 8; r.t.
0.1M Tris / 6M GnHCl; pH 8.5, 4°C or r.t.
0.1M NH₄HCO₃ / 50% TFE; pH 8; r.t.

Recommended peptide concentration = 200-500 μM

GSH / GSSG … reduced / oxidized glutathione

GnHCl … guanidine hydrochloride

DMSO … dimethyl sulfoxide

TFE … 2,2,2-trifluoroethanol

ACN … acetonitrile

i-PrOH … isopropanol