Six novel constitutive promoters for metabolic engineering of Aspergillus niger.
Appl Microbiol Biotechnol
; 97(1): 259-67, 2013 Jan.
Article
em En
| MEDLINE
| ID: mdl-22707054
ABSTRACT
Genetic tools for the fine-tuning of gene expression levels are a prerequisite for rational strain optimization through metabolic engineering. While Aspergillus niger is an industrially important fungus, widely used for production of organic acids and heterologous proteins, the available genetic tool box for this organism is still rather limited. Here, we characterize six novel constitutive promoters of A. niger providing different expression levels. The selection of the promoters was based on published transcription data of A. niger. The promoter strength was determined with the ß-glucuronidase (gusA) reporter gene of Escherichia coli. The six promoters covered a GUS activity range of two to three orders of magnitude depending on the strain background. In order to demonstrate the power of the newly characterized promoters for metabolic engineering, they were used for heterologous expression of the cis-aconitate decarboxylase (cad1) gene of Aspergillus terreus, allowing the production of the building block chemical itaconic acid with A. niger. The CAD activity, dependent on the choice of promoter, showed a positive correlation with the specific productivity of itaconic acid. Product titers from the detection limit to up to 570 mg/L proved that the set of constitutive promoters is a powerful tool for the fine-tuning of metabolic pathways for the improvement of industrial production processes.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Aspergillus niger
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Expressão Gênica
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Regiões Promotoras Genéticas
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Engenharia Metabólica
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Genética Microbiana
Idioma:
En
Revista:
Appl Microbiol Biotechnol
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Áustria