DNA sequences, vectors, and fusion polypeptides to increase secretion of desired polypeptides from filamentous fungi

摘要

The invention includes novel fusion DNA sequences encoding fusion polypeptides which when expressed in a filamentous fungus result in the expression of fusion polypeptides which when secreted result in increased levels of secretion of the desired polypeptide as compared to the expression and secretion of such polypeptides from filamentous fungi transformed with previously used DNA sequences. The fusion DNA sequences comprise from the 5′ terminus four DNA sequences which encode a fusion polypeptide comprising, from the amino to carbonyl-terminus, first, second, third and fourth amino acid sequences. The first DNA sequence encodes a signal peptide functional as a secretory sequence in a first filamentous fungus. The second DNA sequence encodes a secreted polypeptide or portion thereof which is normally secreted from the same filamentous fungus or a second filamentous fungus. The third DNA sequence encodes a cleavable linker polypeptide while the fourth DNA sequence encodes a desired polypeptide. When the fusion DNA sequence is expressed either in the first or second filamentous fungus, increased secretion of the desired polypeptide is obtained as compared to that which is obtained when the desired polypeptide is expressed from DNA sequences encoding a fusion polypeptide which does not contain the second polypeptide normally secreted from either of the filamentous fungi.