Synthesis of thioredoxin partial sequences on 1,6-hexanediol diacrylate (HDODA)-cross-linked polystyrene resin.

The continued and rapid discoveries of new peptides with interesting biological functions have created an unprecedented demand for the chemical synthesis of peptides required for structure-function correlations. Several strategic improvements have been suggested and tested to meet the demand for peptides in high purity and quantity. This article describes the synthesis of three partial sequences of thioredoxin, a naturally occurring sulfur-reducing protein containing 108 amino acid residues, on a newly developed flexible, cross-linked polystyrene support (2% polystyrene cross-linked with 1,6-hexanediol diacrylate) using the standard solid-phase methodology. The protected peptides were cleaved from the polymeric support by trifluoroacetic acid and purified by chromatography. The free peptides were shown to be homogeneous by high-performance liquid chromatography and were characterized by amino acid analysis and circular dichroism. The circular dichroism measurement revealed that the peptides possess a helical conformation. From the yield and purity of the peptides obtained, it was inferred that the favorable swelling and solvation characteristics of the support facilitated effective synthesis.