DNA-sequences coding for two DesPro(2) aprotinin variants were express
ed in the methylotrophic yeast Hansenula polymorpha from a strong indu
cible promoter element derived from the MOX gene, a key gene of methan
ol metabolism. For secretion the coding sequences were fused to the KE
X2 recognition sire of the S. cerevisiae-derived MF alpha 1 preprolead
er sequence. Correct processing of the precursor molecules and efficie
nt secretion of the mature proteins was observed. A pH/pO(2)-controlle
d C-source feeding mode was applied for fermentations on a 10 litre sc
ale. In cultures of a transformant strain harbouring 20 copies of the
aprotinin expression cassette a yield of 350 mg/litre could be obtaine
d. The secreted recombinant products were purified in a simple two-ste
p isolation procedure employing an expanded bed adsorption as an initi
al purification step. Copyright (C) 1996 Elsevier Science Ltd