pSAR1, a natural plasmid from Streptomyces arenae, shows rapid increase and decrease of copy numbers on changes of growth media.

M Braxenthaler; B Poetsch; K U Fröhlich; D Mecke

doi:10.1016/0378-1097(91)90494-u

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pSAR1, a natural plasmid from Streptomyces arenae, shows rapid increase and decrease of copy numbers on changes of growth media.

M Braxenthaler·B Poetsch·K U Fröhlich·D Mecke

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Abstract

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.

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Culture Media DNA, Bacterial Gene Amplification Kinetics Plasmids Streptomyces Journal Article Research Support, Non-U.S. Gov't

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M Braxenthaler, B Poetsch, K U Fröhlich, D Mecke. 1991-10-15. pSAR1, a natural plasmid from Streptomyces arenae, shows rapid increase and decrease of copy numbers on changes of growth media.. https://doi.org/10.1016/0378-1097(91)90494-u

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