Studies of Streptomyces reticuli cel-1 (cellulase) gene expression in Streptomyces strains, Escherichia coli, and Bacillus subtilis

• Published in: Applied and Environmental Microbiology 1995-02, Vol.61 (2), p.487-494
• Main Authors: Walter, S, Schrempf, H
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; amino acid sequences; avicel; avicelase; Bacillus subtilis; Bacillus subtilis - genetics; Bacteria; Base Sequence; Biochemistry; Biological and medical sciences; Biotechnology; cel-1 gene; Cellulase - genetics; Cellulase - metabolism; cellulases; cellulose; cellulose digestion; DNA, Bacterial - genetics; enzyme activity; Enzymes; Escherichia coli; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; genbank/x65616; Gene Expression; gene transfer; Genes, Bacterial; Genetic engineering; Genetic technics; genetic transformation; hydrolysis; Methods. Procedures. Technologies; microcrystalline cellulose; Modification of gene expression level; Molecular Sequence Data; nucleotide sequences; Open Reading Frames; Plasmids - genetics; promoter regions; Promoter Regions, Genetic; Protein Processing, Post-Translational; proteolysis; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Soils; Streptomyces; Streptomyces - enzymology; Streptomyces - genetics; Streptomyces reticuli; structural genes; Transformation, Genetic; zymogens
• ISSN: 0099-2240; 1098-5336
• DOI: 10.1128/aem.61.2.487-494.1995

Various Streptomyces strains [Streptomyces lividans 66, Streptomyces vinaceus, and Streptomyces coelicolor A3 (2)] acquired the ability to utilize crystalline cellulose (Avicel) after transformation with a multicopy vector containing the cel-1 gene from Streptomyces reticuli. The expression level in these hosts was two to three times lower than in S. reticuli, indicating the absence of positive regulatory elements. Like S. reticuli, they processed the Avicelase to its catalytic domain and to an enzymatically inactive part. The cel-1 gene with its original upstream region was not expressed within Escherichia coli. When cel-1 had been fused in phase with the lacZ gene, large quantities of the fusion protein were produced in E. coli. However, this protein was enzymatically inactive and proteolytically degraded to a series of truncated forms. As the cellulase (Avicelase) synthesized by S. reticuli is not cleaved by the E. coli proteases its posttranslational modification is proposed. With Bacillus subtilis as host, the cel-1 gene was expressed neither under its own promoter nor under the control of a strong Bacillus promoter.