title: Evaluation of Aspergillus niger as host for virus-like particle production, using the hepatitis B surface antigen as a model.
abstract: The filamentous fungus Aspergillus niger was transformed with the hepatitis B virus S gene encoding the major viral envelope protein under control of the constitutive A. nidulans glyceraldehyde-3-phosphate dehydrogenase ( gpdA) promoter. Approximately seven copies of the expression cassette were integrated on the genome, resulting in high-level transcription of the S gene. Production of the 24-kDa S protein and a 48-kDa S protein dimer in the membrane-associated protein fraction of the recombinant A. niger strain was shown through Western analysis. Electron microscopy of partially purified recombinant S protein revealed the formation of spherical pseudoviral particles with a diameter of 22 nm. The production level of hepatitis B pseudoviral particles was estimated to be 0.4 mg/l culture, which compares favourably with the reported levels initially obtained in yeast, indicating the potential of the Aspergillus expression system as an alternative, cost-effective vaccine production system.
authors.affiliation: Department of Microbiology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa. whvz@sun.ac.za
authors.forename: Annette
authors.initials: A
authors.lastname: Plüddemann
authors.forename: Willem H
authors.initials: WH
authors.lastname: Van Zyl
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D018628:Gene Dosage; D005818:Genetic Engineering / Q000379:methods*; D006514:Hepatitis B Surface Antigens / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D006515:Hepatitis B virus / Q000302:isolation & purification / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D008957:Models, Genetic; D011401:Promoter Regions, Genetic; D014170:Transformation, Genetic; D019076:Transgenes; D014764:Viral Proteins / Q000235:genetics; D014771:Virion / Q000235:genetics
chemical_list: D006514:Hepatitis B Surface Antigens; D014764:Viral Proteins