Gene expression in Frankia: characterization of promoters.
Promoter regions harbouring typical -10 and -35 sites of prokaryotes were isolated from the genome of various species of Frankia using an Escherichia coli promoter-probe plasmid. These promoter regions initiated transcription in E. coli and Streptomyces cells. The consensus promoter sequence for the -10-like site was T A G/A G G/A T and for the -35-like site was T T G T/A C G. Despite the GC pressure observed in Frankia, functionally important positions in the promoter are conserved. As a consequence of these studies, a marker gene having properties compatible with the transcriptional and translational processes of Frankia was built. It is an npt-II gene under the control of three copies of one of the Frankia-E. coli type promoters studied.
Cournoyer
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B
Laboratoire d'Ecologie Microbienne du Sol, URA CNRS 1450, Université Claude-Bernard Lyon, Villeurbanne, France.
Normand
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P
D000192:Actinomycetales / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation; D010944:Plants / Q000382:microbiology; D011401:Promoter Regions, Genetic / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013559:Symbiosis; D014158:Transcription, Genetic