Purification and DNA-binding properties of human papillomavirus type 16 E6 protein expressed in Escherichia coli.

Unfused human papillomavirus type 16 (HPV 16) E6 protein was expressed in Escherichia coli using a lambda PL promoter system. The protein was isolated from the cells as inclusion bodies, extracted by 6 M guanidine-HCl, and purified by chromatography. The purified protein had high affinity to DNA and was demonstrated for the first time to bind to a specific sequence within the long control region of HPV 16.