Repression and catabolite repression of the lactose operon of Staphylococcus aureus.
The lacR gene encodes the repressor of the lactose operon of S. aureus. The nucleotide sequence of this gene and the promoter-operator region of the operon are reported. The lacR gene encodes a protein with a molecular weight of 28,534. This protein was found to share sequence homology with the DeoR protein, the repressor of the E. coli deoxyribonucleotide operon. Directly and invertedly repeated sequences were found associated with the promoter for the structural genes of the operon. These sequences were examined by site-directed mutagenesis and found to be important in repressor binding and in the binding of a catabolite repressor. Evidence is presented in support of a model for catabolite repression of the operon which involves a negative-acting transcriptional regulator which binds to the promoter region of the operon and prevents transcription.
Oskouian
B
B
Department of Microbiology, University of Kansas, Lawrence 66045.
Stewart
G C
GC
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics; D001483:Base Sequence; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D005821:Genetic Techniques; D005838:Genotype; D007785:Lactose / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D009876:Operon; D012097:Repressor Proteins / Q000235:genetics*; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013211:Staphylococcus aureus / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
D004251:DNA Transposable Elements; D015345:Oligonucleotide Probes; D012097:Repressor Proteins; D014157:Transcription Factors; D007785:Lactose