Cloning and DNA sequence analysis of the wild-type and mutant cyclic AMP receptor protein genes from Salmonella typhimurium
Autor: | W J Dobrogosz, C J Schroeder |
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Rok vydání: | 1986 |
Předmět: |
DNA
Bacterial Salmonella typhimurium Cyclic AMP Receptor Protein Sequence analysis Protein Conformation Mutant Molecular cloning Microbiology Receptors Cyclic AMP Structure-Activity Relationship Plasmid Sequence Homology Nucleic Acid Cyclic AMP Escherichia coli Amino Acid Sequence Cloning Molecular Molecular Biology Gene biology Base Sequence Nucleic acid sequence Molecular biology cAMP receptor protein Biochemistry Genes Bacterial Mutation biology.protein Carbohydrate Metabolism Research Article |
Zdroj: | Journal of bacteriology. 167(2) |
ISSN: | 0021-9193 |
Popis: | The crp gene from Salmonella typhimurium, as well as two mutant adenylate cyclase regulation genes designated crpacr-3 and crpacr-4, were cloned into the EcoRI site of plasmid pUC8. Initially cloned on 5.6-kilobase fragments isolated from EcoRI digests of chromosomal DNA, these genes were further subcloned into the BamHI-EcoRI site of plasmid pBR322. When tested, Escherichia coli crp deletion strains harboring the clones regained their ability to pleiotropically ferment catabolite-repressible sugars. Also, the crpacr-containing strains displayed sensitivity to exogenous cyclic AMP (cAMP) when grown on eosin-methylene blue medium with xylose as the carbon source. The proteins encoded by the S. typhimurium wild-type and mutant crp genes were found to have similar molecular weights when compared with the wild-type cAMP receptor protein (CRP) from E. coli. DNA sequence analysis of the wild-type crp gene showed only a three-nucleotide difference from the E. coli sequence, suggesting little divergence of the crp gene between these organisms. The crpacr sequences, however, each contained single nucleotide changes resulting in amino acid substitutions at position 130 of the CRP. Based on the site at which these substitutions occur, the crpacr mutations are believed to affect CRP-cAMP interactions. |
Databáze: | OpenAIRE |
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