Promoter analysis of the staphylococcal enterotoxin A gene.
The promoter region of the staphylococcal enterotoxin A (SEA) gene (sea) of Staphylococcus aureus was localized by primer extension analysis in conjunction with in vitro mutagenesis. The 5'-end of sea mRNA was located 86 base pairs upstream of the translational initiation codon. A DNA region with good agreement with canonical promoter sequences was observed beginning 8 base pairs upstream of the apparent transcriptional start site. Analysis of a series of progressive deletions of upstream DNA revealed that no DNA upstream of the putative -35 region was required for transcription of sea (determined by primer extension analysis) or for SEA production as detected by Western immunoblot analysis. Deletion mutants extending into the -35 region or mutants containing nucleotide substitutions in the -10 region both showed dramatic reductions in SEA production and transcription of sea. Analysis of a deletion mutant in which 59 base pairs between the transcriptional and translational start sites were deleted revealed slightly increased levels of SEA production.
Borst
D W
DW
Department of Bacteriology, University of Wisconsin, Madison 53706.
Betley
M J
MJ
D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D017931:DNA Primers; D004269:DNA, Bacterial / Q000032:analysis / Q000378:metabolism; D004768:Enterotoxins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D004926:Escherichia coli; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D015183:Restriction Mapping; D017384:Sequence Deletion; D013211:Staphylococcus aureus / Q000235:genetics*
D017931:DNA Primers; D004269:DNA, Bacterial; D004768:Enterotoxins; C026066:enterotoxin A, Staphylococcal