Fusion Expression and
Purification of OSBP PH Domain and Preliminary Analysis of Its Second Stucture
SHEN Lan, JI Shao-Ping, NIE Xiao-Yan, LIU Xin-Ping, YAO
Li-Bo*
( Department of Biochemstry and Molecular Biologhy, Fourth Military Medical
University, Xi’an 710032, China )
Abstract Oxysterol
binding protein (OSBP) is a regulator of oxysteroid metabolism. To investigate
the function and the structure-function relationship of OSBP, the recombinant
vector OSBP PH-pRSET-A was transformed into E.coli
JM109(DE3), and the strain highly expressing soluble 6His-OSBP PH domain in
minimal medium were obtained. The fusion protein was purified by Ni2＋-NTA agarose beads. The
secondary structure of the purified 6His-OSBP PH domain fusion protein was
analysed by circular dichronism. The results indicated the PH domain was
composed of α-helix 7.2%, β-pleated sheets 71.1% and radom coil 21.7%.
Key words OSBP； PH domain； metal chelate affinity
chromatography； minimal media； circular dichronism
*Corresponding author： Tel, 86-29-3374513；e-mail, [email protected]