Efficient KEX2-like processing of a glucoamylase-interleukin-6 fusion protein by Aspergillus nidulans and secretion of mature interleukin-6.
We have designed an expression vector for the secretion of human interleukin-6 (hIL-6) in which the mature protein is fused through a spacer peptide, containing a KEX-2 like protein processing signal, to the entire Aspergillus niger glucoamylase (glaA) gene. Transformation of Aspergillus nidulans with this vector results in fungal strains secreting equimolar amounts of the glucoamylase and IL-6 proteins. The KEX2-type processing signal, Lys-Arg, is recognized and cleaved efficiently by an enzyme present in A. nidulans resulting in the secretion of an authentic mature hIL-6 protein at levels of up to 5 mg/l.
Laboratory of Molecular Biology, State University, Gent, Belgium.
R
R
Contreras
D
D
Carrez
J R
JR
Kinghorn
C A
CA
van den Hondel
W
W
Fiers
D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000235:genetics*; D001234:Aspergillus niger / Q000201:enzymology; D001483:Base Sequence; D015153:Blotting, Western; D004591:Electrophoresis, Polyacrylamide Gel; D010450:Endopeptidases / Q000378:metabolism*; D005822:Genetic Vectors; D005087:Glucan 1,4-alpha-Glucosidase / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics* / Q000378:metabolism; D008024:Ligands; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D043484:Proprotein Convertases; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis*; D029701:Saccharomyces cerevisiae Proteins; D012697:Serine Endopeptidases; D013381:Subtilisins
D015850:Interleukin-6; D008024:Ligands; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D005087:Glucan 1,4-alpha-Glucosidase; D010450:Endopeptidases; D043484:Proprotein Convertases; D012697:Serine Endopeptidases; D013381:Subtilisins; C058751:KEX2 protein, S cerevisiae