Double disruption of the proteinase genes, tppA and pepE, increases the production level of human lysozyme by Aspergillus oryzae.


Journal Article

In this study, we investigated the effects of proteinase gene disruption on heterologous protein production by Aspergillus oryzae. The human lysozyme (HLY) was selected for recombinant production as a model for the heterologous protein. A tandem HLY construct fused with alpha-amylase (AmyB) was expressed by A. oryzae in which the Kex2 cleavage site was inserted at the upstream of HLY. HLY was successfully processed from AmyB and produced in the medium. We performed a systematic disruption analysis of five proteinase genes (pepA, pepE, alpA, tppA, and palB) in the HLY-producing strain with the adeA selectable marker. Comparative analysis indicated that disruption of the tppA gene encoding a tripeptidyl peptidase resulted in the highest increase (36%) in the HLY production. We further deleted the tppA gene in the pepE or palB disruptant with another selectable marker, argB. Consequently, a double disruption of the tppA and pepE genes led to a 63% increase in the HLY production compared to the control strain. This is the first study to report that the double disruption of the tppA and pepE genes improved the production level of a heterologous protein by filamentous fungi.

Full Text

Duke Authors

Cited Authors

  • Jin, FJ; Watanabe, T; Juvvadi, PR; Maruyama, J-I; Arioka, M; Kitamoto, K

Published Date

  • October 2007

Published In

Volume / Issue

  • 76 / 5

Start / End Page

  • 1059 - 1068

PubMed ID

  • 17622525

Pubmed Central ID

  • 17622525

International Standard Serial Number (ISSN)

  • 0175-7598

Digital Object Identifier (DOI)

  • 10.1007/s00253-007-1088-4


  • eng

Conference Location

  • Germany