Some factors influencing the proportion of periplasmic hepatitis B virus pre-S2 antigen in the recombinant yeast Hansenula polymorpha.
A central composite design (CCD) was used to evaluate, for the purpose of future process optimization, the influence of pH, yeast extract and ammonium chloride concentrations on the proportion of periplasmic hepatitis B pre-S2 antigen in the recombinant yeast Hansenula polymorpha. Each factor was tested at five levels, and a second order polynomial model for the proportion of periplasmic antigen was fitted to the treatment combinations. pH showed the greatest effect: the proportion of periplasmic antigen was greatly increased at the higher pH levels. At the higher pH levels used, the proportion of periplasmic antigen was enhanced by a high concentration of ammonium chloride. Additional experiments have confirmed both the validity of the selected model and the optimal conditions found. A significant correlation was found between the proportion of periplasmic antigen and the total yield of antigen. These results indicated that it should be possible to modulate the distribution of the pre-S2 antigen between the periplasm and the cytoplasm of the yeast.
National Research Council of Canada, Biotechnology Research Institute, Montreal, Quebec.
M R
MR
de Roubin
M D
MD
Cailas
S H
SH
Shen
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D
Groleau
D000643:Ammonium Chloride / Q000494:pharmacology; D003470:Culture Media; D006514:Hepatitis B Surface Antigens / Q000096:biosynthesis* / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D008954:Models, Biological; D010843:Pichia / Q000235:genetics / Q000276:immunology*; D011498:Protein Precursors / Q000096:biosynthesis* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000096:biosynthesis; D014759:Viral Envelope Proteins / Q000096:biosynthesis* / Q000302:isolation & purification
D003470:Culture Media; D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins; C050807:presurface protein 2, hepatitis B surface antigen; D000643:Ammonium Chloride