中国生物工程杂志

In the present work we have studied if Eudragit S-100, a pH-responsive polymer can enhance the refolding level of TGF-β1 (Transforwing growth factor，TGF-β1). The refolding of TGF-β1 was performed by directly diluting denatured TGF-β1 into a refolding buffer containing different concentration of Eudragit. The ability of Eudragit S-100 to enhance protein refolding level was investigated using MTT assay, reverse phase HPLC, fluorescence emission spectroscopy and circular dichroism spectroscopy. The addition of Eudragit S-100 in the refolding buffer significantly increases TGF-β1 refolding yield to 53%, when dilution refolding was conducted at 0.5 mg/ml TGF-β1. This study shows evidence of an electrostatic interaction between oppositely charged TGF-β1 and the Eudragit polymer during refolding. This ionic complexing of Eudragit and TGF-β1 appears to shield exposed hydrophobic residues of the lysozyme refolding intermediates, thus minimizing hydrophobic-driven aggregation of the molecules.