Hyperexpression of a Bacillus circulans xylanase gene in Escherichia coli and characterization of the gene product.
AUTOR(ES)
Yang, R C
RESUMO
A 4.0-kilobase (kb) fragment of Bacillus circulans genomic DNA inserted into pUC19 and encoding endoxylanase activity was subjected to a series of subclonings. A 1.0-kb HindIII-HincII subfragment was found to code for xylanase activity. Maximum expression levels were observed with a subclone that contained an additional 0.3-kb sequence upstream from the coding region. Enhancer sequences in the upstream region are thought to be responsible for these high expression levels. Southern hybridization analyses revealed that the cloned gene hybridized with genomic DNA from Bacillus subtilis and Bacillus polymyxa. Xylanase activity expressed by Escherichia coli harboring the cloned gene was located primarily in the intracellular fraction. Levels of up to 7 U/ml or 35 mg/liter were obtained. The protein product was purified by ion exchange and gel permeation chromatography. The xylanase had a molecular weight of 20,500 and an isoelectric point of 9.0.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=184275Documentos Relacionados
- Xylanase from the extremely thermophilic bacterium "Caldocellum saccharolyticum": overexpression of the gene in Escherichia coli and characterization of the gene product.
- Hyperexpression of two Aspergillus niger xylanase genes in Escherichia coli and characterization of the gene products
- Structural and biochemical characterization of the Escherichia coli argE gene product.
- Nucleotide sequence of a Bacillus circulans xylanase gene.
- Characterization of the Escherichia coli thyA gene and its amplified thymidylate synthetase product.
