Identification and characterization of a locus inhibiting extrachromosomal maintenance of the Streptomyces plasmid SLP1.
We report here the existence and initial characterization of a genetic locus (imp) that inhibits maintenance of SLP1-derived plasmids as extrachromosomal replicons in a manner distinct from normal incompatibility between autonomous SLP1 replicons. The trans-acting imp function has been localized to a 1.8 kb Eco47III restriction fragment present on integrated SLP1 elements. At least part of this DNA segment is absent from SLP1-derived plasmids. DNA sequence analysis of the imp region indicates that it contains three overlapping open reading frames (ORFs) that may constitute a polycistronic operon. The effects of insertions within the imp region indicate that uninterrupted transcription through all three ORFs is necessary for imp activity.
Grant
S R
SR
Department of Genetics, Stanford University School of Medicine, CA 94305.
Lee
S C
SC
Kendall
K
K
Cohen
S N
SN
D000595:Amino Acid Sequence; D001483:Base Sequence; D002872:Chromosome Deletion; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010957:Plasmids; D012093:Replicon; D015183:Restriction Mapping; D013302:Streptomyces / Q000235:genetics*
D004269:DNA, Bacterial; D004268:DNA-Binding Proteins