Open AccessThis article is
- freely available
Optimal Cleavage and Oxidative Folding of α-Conotoxin TxIB as a Therapeutic Candidate Peptide
Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drug of Haikou, Hainan University, Haikou, Hainan 570228, China
* Authors to whom correspondence should be addressed.
Received: 5 August 2013; in revised form: 16 August 2013 / Accepted: 19 August 2013 / Published: 17 September 2013
(This article belongs to the Special Issue Conotoxins
Abstract: Alpha6beta2 nicotinic acetylcholine receptors (nAChRs) are potential therapeutic targets for the treatment of several neuropsychiatric diseases, including addiction and Parkinson’s disease. Alpha-conotoxin (α-CTx) TxIB is a uniquely selective ligand, which blocks α6/α3β2β3 nAChRs only, but does not block the other subtypes. Therefore, α-CTx TxIB is a valuable therapeutic candidate peptide. Synthesizing enough α-CTx TxIB with high yield production is required for conducting wide-range testing of its potential medicinal applications. The current study optimized the cleavage of synthesized α-CTx TxIB resin-bounded peptide and folding of the cleaved linear peptide. Key parameters influencing cleavage and oxidative folding of α-CTx TxIB were examined, such as buffer, redox agents, pH, salt, co-solvent and temperature. Twelve conditions were used for cleavage optimization. Fifty-four kinds of one-step oxidative solution were used to assess their effects on each α-CTx TxIB isomers’ yield. The result indicated that co-solvent choices were particularly important. Completely oxidative folding of globular isomer was achieved when the NH4HCO3 or Tris-HCl folding buffer at 4 °C contained 40% of co-solvent DMSO, and GSH:GSSG (2:1) or GSH only with pH 8~8.7.
Keywords: α-conotoxin TxIB; oxidative folding; optimization; therapeutic peptides
Citations to this Article
Cite This Article
MDPI and ACS Style
Wu, X.; Wu, Y.; Zhu, F.; Yang, Q.; Wu, Q.; Zhangsun, D.; Luo, S. Optimal Cleavage and Oxidative Folding of α-Conotoxin TxIB as a Therapeutic Candidate Peptide. Mar. Drugs 2013, 11, 3537-3553.
Wu X, Wu Y, Zhu F, Yang Q, Wu Q, Zhangsun D, Luo S. Optimal Cleavage and Oxidative Folding of α-Conotoxin TxIB as a Therapeutic Candidate Peptide. Marine Drugs. 2013; 11(9):3537-3553.
Wu, Xiaosa; Wu, Yong; Zhu, Furong; Yang, Qiuyuan; Wu, Qianqian; Zhangsun, Dongting; Luo, Sulan. 2013. "Optimal Cleavage and Oxidative Folding of α-Conotoxin TxIB as a Therapeutic Candidate Peptide." Mar. Drugs 11, no. 9: 3537-3553.