Patent ID: 7429385

Claim:
A method for isolating a hepatitis C virus (HCV) E1 polypeptide that lacks a portion of its C-terminus, wherein the HCV E1 polypeptide terminates at amino acid position 300, 330, 350, 360, 370, 351, 352, or 353, numbered with reference to the HCV1 polyprotein amino acid sequence, said method comprising: (a) providing a population of host cells transformed with a polynucleotide comprising a coding sequence, wherein said coding sequence consists of a sequence coding for said HCV E1 polypeptide, wherein said coding sequence is operably linked to control elements such that said coding sequence can be transcribed and translated in the host cell, wherein the N-terminus of the E1 polypeptide is amino acid 192 or 173, or a methionine directly followed by an isoleucine and amino acid 172, numbered with reference to the HCV1 polyprotein amino acid sequence; (b) culturing said population of cells under conditions whereby said HCV E1 polypeptide is expressed intracellularly; (c) disrupting said host cells; and (d) isolating said HCV E1 polypeptide from within said disrupted cells by a method that preserves the native conformation of the E1 polypeptide.