A relationship between the starting secondary structure of recombinant porcine growth hormone solubilised from inclusion bodies and the yield of native (monomeric) protein after in vitro refolding

FEBS Letters

Cardamone, M.¹  Puri, N.K.¹ 

[1] Centre for Animal Biotechnology, School of Veterinary Science, The University of Melbourne, Parkville Victoria 3052, Australia

关键词: In vitro refolding;    Secondary structure;    Cationic surfactant;    Growth hormone;    Inclusion body;   

DOI  :  10.1016/0014-5793(92)80661-Y

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Recombinant porcine growth hormone (rPGH) was solubilised from inclusion bodies (IB's) using either 6 M guanidinium hydrochloride (GnHCl), 7.5 M urca or by a novel method using a cationic surfactant, cetyltrimethylammonium chloride (CTAC). Circular dichroism (CD) analysis of the secondary (2°) structure of the urea- and GnHCl-solubilised rPGH showed the absence of α-helical content with the majority of the molecule existing in a ‘random coil’ structure. In contrast, the CTAC-solubilised rPGH displayed significant starting 2° structure (10–15% α helix; 30–40% β structure). The three rPGH preparations were refolded in vitro against weak urea, GnHCl or aqueous buffers, resulting in an average refolding efficiency of 50% native (monomeric) rPGH for CTAC solubilised IB's and only 20% for urea or GnHCl solubilised IB's. We conclude that the method of solubilisation of IB's and the resultant difference in the starting 2° structure of rPGH, particularly α-helical content, is a major in vitro factor that apparently predetermines the aggregation/refolding behaviour rPGH irrespective of refolding environment.

【 授权许可】

Unknown