Data on the optimizations of expression and purification of human BiP/GRP78 protein in Escherichia coli.

Human BiP/GRP78 is involved in the folding and assembly of proteins in the endoplasmic reticulum. The proteins for crystallization in good amount and quality are prerequisites for obtaining ideal crystals. To meet these requirements, different BiP/GRP78 constructs, competent cells, vectors, and concentrations of inducer were tested in order to obtain soluble BiP/GRP78 protein with the highest amount and best purity. The BiP-T229A-L3,4'-Smt3 fusion protein was expressed in a soluble manner and finally purified with the highest purity using size exclusion chromatography, which was suitable for further protein crystallization.