Mutagenic analysis of the promoter of the Streptomyces fradiae beta-lactamase-encoding gene.
The Streptomyces fradiae beta-lactamase promoter (PblaF) was sequenced and characterized by promoter probing, primer extension, and exonuclease III-mediated deletions. The transcription start point (tsp) was the same in both S. lividans and S. fradiae. Oligodeoxyribonucleotide-directed random mutations and site-specific mutations were introduced in the promoter region. The effects of these mutations on transcription were assayed by an RNA colony hybridization method. This analysis identified cis-acting sequence determinants located similarly to the -10 and -35 regions of a typical Escherichia coli promoter. Also, a change in the distance between these regions from 19 to 17 bp drastically reduced promoter activity. PblaF was shown not to be recognized by sigma-whiG or by sigma-hrdA, hrdC, or hrdD. Sequence alignment of PblaF to sigma factor-classified Streptomyces promoters revealed little homology. Thus, PblaF is probably recognized by an as yet unidentified sigma factor.
Forsman
M
M
Department of Microbiology, National Defence Research Establishment, Umeå, Sweden.
Granström
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D004269:DNA, Bacterial; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009693:Nucleic Acid Hybridization; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000378:metabolism; D012808:Sigma Factor / Q000378:metabolism; D013302:Streptomyces / Q000201:enzymology / Q000235:genetics*; D014158:Transcription, Genetic; D001618:beta-Lactamases / Q000235:genetics*
D004269:DNA, Bacterial; D012329:RNA, Bacterial; D012808:Sigma Factor; D001618:beta-Lactamases