Construction of α-amylase-producing strains not subject to carbon catabolite repression

• Published in: FEMS microbiology letters Vol. 206; no. 2; pp. 157 - 162
• Main Authors: Mellouli, Lotfi, Karray-Rebai, Ines, Bejar, Samir
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 10.01.2002; Blackwell
• Subjects: adverse effects; Affinity; alpha-amylase; alpha-Amylases; alpha-Amylases - biosynthesis; alpha-Amylases - genetics; Bacteriology; Biological and medical sciences; biosynthesis; carbon; Cloning, Molecular; Enzyme Repression; enzymology; Fundamental and applied biological sciences. Psychology; Gene Dosage; Gene expression; Gene Expression Regulation, Bacterial; genes; Genes, Bacterial; Genetic Vectors; Genetics; glucose; Glucose - pharmacology; glycerol; Glycerol - pharmacology; High copy number; LacI-like regulator; Microbiology; pharmacology; plasmids; promoter regions; Promoter Regions, Genetic; Streptomyces; Streptomyces - enzymology; Streptomyces - genetics; Streptomyces lividans; transcription factors; α-Amylase; Affinity; α-Amylase; Gene expression; LacI-like regulator; High copy number; Streptomycetaceae; Enzyme; Copy number; Glycerol; Streptomyces; Transcription repressor; Glucose; Dyatic symmetric element; Actinomycetales; Glycosidases; Streptomyces lividans; Bacteria; Hydrolases; Actinomycetes; O-Glycosidases; Vector; Catabolic repression
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/S0378-1097(01)00520-1

The dyatic symmetric element (DSE) present in the α-amylase gene promoter region of the thermophilic Streptomyces strain sp. TO1, and the whole α-amylase gene ( amy TO1) with a 3-bp change in the DSE, were cloned in the high copy number replicative cloning vector pIJ702 giving pLM10 and pLM11 plasmids respectively. In TO1/pLM10 and Streptomyces lividans TK24/pLM11 strains, the expression of α-amylase TO1 gene became insensible to the negative effect of glucose and glycerol. These results strongly suggest that, in a high copy number system, the negative transcriptional regulator was titrated out by the DSE and the repression of the expression of amy TO1 gene is abolished.