pSAR1, a natural plasmid from Streptomyces arenae, shows rapid increase and decrease of copy numbers on changes of growth media.
A natural plasmid, pSAR1, was isolated from the antibiotic producer Streptomyces arenae TU469. Its size is estimated to approx. 80 kbp by restriction analysis. pSAR1 occurs in two copy-number states differing by a factor of at least 10, depending on culture conditions. The high copy-number state is strongly correlated with the production of the antibiotic pentalenolactone. The decrease of copy numbers after change of culture conditions is completed within 1 h. These unusually rapid kinetics and the occurrence of degradational intermediates suggest the participation of specific catalytic mechanisms in copy number regulation.
Braxenthaler
M
M
Physiologisch-chemisches Institut, University of Tübingen, F.R.G.
Poetsch
B
B
Fröhlich
K U
KU
Mecke
D
D
D003470:Culture Media; D004269:DNA, Bacterial / Q000378:metabolism; D005784:Gene Amplification; D007700:Kinetics; D010957:Plasmids; D013302:Streptomyces / Q000235:genetics* / Q000254:growth & development
D003470:Culture Media; D004269:DNA, Bacterial