Identification of polymerized-albumin receptor domain in the pre-S2 region of hepatitis B virus surface antigen M protein.
The pre-S2-coding region in the hepatitis B virus surface antigen M (P31; pre-S2 + S) protein gene was modified to identify a polymerized-albumin receptor (PAR) domain by deleting restriction fragments or performing site-directed mutagenesis. The modified M protein genes (M-P31x; x = d, e, f, h and i) were cloned into the yeast generalized-expression vector pGLD 906-1 and expressed in Saccharomyces cerevisiae under the control of yeast glyceraldehyde-3-phosphate dehydrogenase gene promoter. The PAR activities of these gene products suggested that the PAR domain is located in the hydrophilic and highly conserved domain in the pre-S2 region (around Leu12 approximately Tyr21). Antibodies specific for a pre-S2 peptide (Phe8 approximately Pro34, subtype adr), which covers the PAR domain, were purified from sera of rabbits immunized with yeast-derived M protein particles having a natural PAR domain. Immune electron microscopy showed that the purified antibodies could aggregate HBV particles. Therefore, it was speculated that the PAR domain overlapped with the dominant virus-neutralizing and virus-protecting epitopes.
Biology Research Laboratories, Takeda Chemical Industries, Ltd., Osaka, Japan.
Y
Y
Itoh
S
S
Kuroda
T
T
Miyazaki
S
S
Otaka
Y
Y
Fujisawa
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001704:Biopolymers; D006510:Hepatitis B Antibodies / Q000502:physiology; D006514:Hepatitis B Surface Antigens / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D006515:Hepatitis B virus / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D010957:Plasmids; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D011817:Rabbits; D011940:Receptor Aggregation / Q000276:immunology; D017457:Receptors, Albumin; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D012709:Serum Albumin / Q000737:chemistry* / Q000235:genetics; D014771:Virion / Q000276:immunology
D001704:Biopolymers; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; D017457:Receptors, Albumin; D011956:Receptors, Cell Surface; D012709:Serum Albumin; C050807:presurface protein 2, hepatitis B surface antigen