title: Development of an efficient production method for beta-mannosidase by the creation of an overexpression system in Aspergillus aculeatus.
abstract: OBJECTIVE
  To develop an overexpression system in Aspergillus aculeatus in order to establish an efficient overproduction method of beta-mannosidase (MANB).
  
  
  RESULTS
  An overexpression plasmid for the manB gene, encoding A. aculeatus MANB, was constructed and introduced into A. aculeatus cells. The gene was overexpressed under an improved promoter containing 12 copies of Region III cis-elements of Aspergillus oryzae in the transformant, and it secreted 2.56 mg MANB ml(-1) in liquid culture, which obtained a 9.4-fold higher productivity than that achieved in an overexpression system in A. oryzae. Most of the secreted protein in the cultured medium of the transformed A. aculeatus was the overproduced enzyme.
  
  
  CONCLUSIONS
  Aspergillus aculeatus with the introduced overexpression plasmid produced 2.56 mg MANB ml(-1) in cultured medium. The improved promoter with A. oryzae Region III functioned in A. aculeatus; thus the strain is an expectant host for recombinant protein productions.
  
  
  CONCLUSIONS
  The overexpression system with the improved promoter in A. aculeatus brought the highest productivity of MANB reported to date. The expression system would be a strong bioindustrial tool for protein production.
authors.affiliation: Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Kanagawa, Japan. byy02101@nifty.com
authors.forename: S
authors.initials: S
authors.lastname: Kanamasa
authors.forename: T
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: G
authors.initials: G
authors.lastname: Takada
authors.forename: S
authors.initials: S
authors.lastname: Kajiwara
authors.forename: J
authors.initials: J
authors.lastname: Sumitani
authors.forename: M
authors.initials: M
authors.lastname: Arai
mesh_terms: D001230:Aspergillus / Q000145:classification / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D001709:Biotechnology / Q000379:methods*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D014170:Transformation, Genetic; D015854:Up-Regulation; D044902:beta-Mannosidase / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D011994:Recombinant Proteins; D044902:beta-Mannosidase