This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Lovett, P. S. Search for Related Content PubMed PubMed Citation Articles by Lovett, P. S.

Plasmid in Bacillus pumilus and the Enhanced Sporulation of Plasmid-Negative Variants

¹ Department of Biological Sciences, University of Maryland at Baltimore, Catonsville, Maryland 21228

ABSTRACT

Approximately 3% of the deoxyribonucleic acid (DNA) of Bacillus pumilus NRS576 can be isolated as covalently closed, circular duplex molecules of homogeneous size. The mol wt of the 576 plasmid is approximately 30 million. NRS576 (plasmid⁺) is oligosporogenic; less than 1% of the cells form spores during incubation in liquid AK sporulation medium. Variants that form spores at a high frequency (greater than 50% spores in 24 h) occur spontaneously at a frequency of approximately 10^–5. More than 25 such variants have been examined and all lack detectable plasmid DNA. A relationship appears to exist between the oligosporogenic properties of NRS576 and the presence of the 576 plasmid.