title: Cloning and growth-regulated expression of the gene encoding the hepatitis B virus middle surface antigen in Yarrowia lipolytica.
abstract: Expression of the gene encoding the hepatitis B virus middle surface antigen (pre-HBsAg) in the yeast Yarrowia lipolytica has been studied. The preS2-HBsAg gene was expressed from the alkaline extracellular protease-encoding gene (XPR2) promoter. In the fusion construct, the membrane-spanning 'a' domain of preS2-HBsAg has been replaced by the leader peptide and the proI region of the alkaline protease, thus eliminating the epitope responsible for the immune escape mechanism. Expression has been found to be growth-stage dependent with the highest protein accumulation during the stationary phase, accounting for around 2.35% of the total soluble intracellular proteins. The produced protein was assembled into Dane particles and was immunogenic in mice. The expression vector was found to be stable for at least 100 generations under non-selective conditions.
authors.affiliation: Department of Microbiology, Faculty of Science, M.S. University of Baroda, India.
authors.forename: P V
authors.initials: PV
authors.lastname: Hamsa
authors.forename: B B
authors.initials: BB
authors.lastname: Chattoo
mesh_terms: D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D015966:Gene Expression Regulation, Fungal / Q000502:physiology; D005814:Genes, Viral; D005822:Genetic Vectors; D006514:Hepatitis B Surface Antigens / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D017325:Hepatitis B Vaccines / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D010957:Plasmids; D011498:Protein Precursors / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000276:immunology; D004718:Saccharomycetales / Q000235:genetics* / Q000254:growth & development; D012697:Serine Endopeptidases / Q000235:genetics; D014614:Vaccines, Synthetic / Q000276:immunology
chemical_list: D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; D014614:Vaccines, Synthetic; C050807:presurface protein 2, hepatitis B surface antigen; D012697:Serine Endopeptidases; C067468:Yarrowia lipolytica alkaline extracellular protease