title: The global regulator LaeA controls production of citric acid and endoglucanases in Aspergillus carbonarius.
abstract: The global regulatory protein LaeA is known for regulating the production of many kinds of secondary metabolites in Aspergillus species, as well as sexual and asexual reproduction, and morphology. In Aspergillus carbonarius, it has been shown that LaeA regulates production of ochratoxin. We have investigated the regulatory effect of LaeA on production of citric acid and cellulolytic enzymes in A. carbonarius. Two types of A. carbonarius strains, having laeA knocked out or overexpressed, were constructed and tested in fermentation. The knockout of laeA significantly decreased the production of citric acid and endoglucanases, but did not reduce the production of beta-glucosidases or xylanases. The citric acid accumulation was reduced with 74-96 % compared to the wild type. The endoglucanase activity was reduced with 51-78 %. Overexpression of LaeA seemed not to have an effect on citric acid production or on cellulose or xylanase activity.
authors.affiliation: Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark.
authors.forename: Tore
authors.initials: T
authors.lastname: Linde
authors.affiliation: Carlsberg Research Laboratory, Yeast & Fermentation, Group Commercial, Gamle Carlsberg Vej 4, 1799, Copenhagen V, Denmark.
authors.forename: Marta
authors.initials: M
authors.lastname: Zoglowek
authors.affiliation: Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Lübeck
authors.affiliation: DTU, Institute for System-biologi, Fungal Chemodiversity, Søltofts Plads, 2800, Kgs. Lyngby, Denmark.
authors.forename: Jens Christian
authors.initials: JC
authors.lastname: Frisvad
authors.affiliation: Section for Sustainable Biotechnology, Aalborg University, A.C. Meyers Vaenge 15, 2450, Copenhagen SV, Denmark. psl@bio.aau.dk.
authors.forename: Peter Stephensen
authors.initials: PS
authors.lastname: Lübeck
mesh_terms: D001230:Aspergillus / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D044602:Cellulases / Q000378:metabolism*; D019343:Citric Acid / Q000378:metabolism*; D005285:Fermentation; D008780:Methyltransferases / Q000235:genetics / Q000502:physiology*
chemical_list: D019343:Citric Acid; D008780:Methyltransferases; D044602:Cellulases
keywords: Aspergillus carbonarius; Cellulases; Citric acid; LaeA; Metabolic engineering