ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract We constructed a plasmid that directs the synthesis and secretion of hepatitis B virus (HBV) surface antigen (HBsAg) particles by Saccharomyces cerevisiae. This plasmid contains a proteinase-resistant HBsAg M (M-P31c) gene fused at its 5'-terminus with a chicken-lysozyme signal peptide (C-SIG) gene, which is placed under the yeast GLD (glyceraldehyde-3-phosphate dehydrogenese gene) promoter. The products encoded by the “C-SIG + M-P31c” (LM-P31c) gene were synthesized and assembled themselves into HBsAg particles in yeast cells, and the particles were released into the medium along with poly-HSA (polymerized human serum albumin) binding activity. The HBsAg particles purified from the medium were very similar in density (1.19 g cm−3), size (19.2±0.8 nm in diameter) and shape (sphere) to human-plasma-derived HBsAg particles. When several sec (temperature-sensitive secretion-defective) mutants were used as host cells, the release of HBsAg particles into the medium was blocked at 37°C but not at 25°C, indicating that the HBsAg particles are exported through the normal yeast secretion pathway. To our knowledge, this is the first report that yeast cells are capable of secreting particles into the medium.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00170389
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