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Updated: Apr 20, 2026

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library
Published on: June 20, 2014
Refolding additive, dimethylbenzylammonium propane sulfonate (NDSB- 256), accelerates gly-pro cis-trans isomerization
Haimei Wang, Kazuo Hosoda, Shin-Ichi Terawaki
11-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan. kwakamats@gunma-u.ac.jp.
Abstract:
Proline cis-trans isomerization plays a key role in the rate-determining steps of protein folding, and many different peptide-proline cis-trans isomerases (PPIases) catalyze this reaction. The acceleration of isomerization would be beneficial for in vitro refolding of protein preparations for industrial and research purposes. So we analyzed whether low-molecular-weight compounds that have been reported to enhance protein refolding have the activity to accelerate the isomerization. To evaluate the effects of chemicals on the isomerization rate, we set up a new NMR (EXSY) method that is invulnerable to their inhibitory activity, if any, and to their large NMR signals. With this method, we found that dimethylbenzylammonium propane sulfonate (NDSB-256) increase the isomerization rate in a concentration-dependent manner for the first time. Acceleration by imidazole (suggested but not experimentally confirmed) was also demonstrated. Arginine, a most popular refolding additive, did not show any significant effects on the isomerization reaction as expected.
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