title: Evaluation of the catalase promoter for expressing the alkaline xylanase gene (alx) in Aspergillus niger.
abstract: Aspergillus niger represents a promising host for the expression of recombinant proteins, but only a few expression systems are available for this organism. In this study, the inducible catalase promoter (PcatR) from A. niger was characterized. For this, constructs were developed and checked for the expression of the alkaline xylanase gene transcriptionally fused under the cat R promoter. Two versions of the catalase (catR) promoter sequence from A. niger (P(cat300,) P(cat924)) were isolated and tested for their ability to drive expression of the alkaline xylanase (alx) gene. P(cat924) showed better efficiency (more than 10-fold increase in AlX activity compared to P(cat300)) under the optimized culture conditions. Induction of the catR promoter with 0.20% H(2)O(2) and 1.5% CaCO(3) in the culture medium, further increased expression of AlX 2.61- and 2.20-fold, respectively, clarifying its inducible nature. Specific induction or repression of the catR promoter provides the possibility for utilization of this promoter in heterologous protein production.
authors.affiliation: Biotechnology Division, Indian Institute of Integrative Medicine (CSIR), Jammu, India.
authors.forename: Ruchika
authors.initials: R
authors.lastname: Sharma
authors.forename: Meenu
authors.initials: M
authors.lastname: Katoch
authors.forename: Nagraj
authors.initials: N
authors.lastname: Govindappa
authors.forename: P S
authors.initials: PS
authors.lastname: Srivastava
authors.forename: Kedarnath N
authors.initials: KN
authors.lastname: Sastry
authors.forename: Ghulam Nabi
authors.initials: GN
authors.lastname: Qazi
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002374:Catalase / Q000235:genetics* / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000235:genetics* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic
chemical_list: D005656:Fungal Proteins; D002374:Catalase; D043364:Endo-1,4-beta Xylanases