Characteristics of hepatitis B surface antigen produced in yeast.
We have constructed an expression plasmid for regulated expression of the hepatitis B surface antigen gene in yeast using promoter of the yeast Pho5 gene. In the yeast transformants, the monomeric HBsAg (22K dalton) was estimated to constitute approximately 3% of the total proteins. On extraction, the HBsAg was found to have a buoyant density of 1.18 g/ml and an Sw.20 value of 54. Electron microscopy revealed particles of heterogeneous size ranging from 18-28 nm. When the yeast HBsAg was used to immunize guinea pigs, the anti-HBsAg antibodies produced could react with human serum HBsAg.
D000818:Animals; D002499:Centrifugation, Density Gradient; D004274:DNA, Recombinant; D006168:Guinea Pigs; D006514:Hepatitis B Surface Antigens / Q000235:genetics* / Q000276:immunology; D008854:Microscopy, Electron; D009876:Operon; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D014170:Transformation, Genetic
D004274:DNA, Recombinant; D006514:Hepatitis B Surface Antigens