The plasmids found in isolates of the acidothermophilic archaebacterium Thermoplasma acidophilum

Plasmids were detected in isolates of an acidothermophilic archaebacterium Thermoplasma acidophilum. One of the plasmids, pTA1, was characterized. The plasmid was a circular DNA of 15.2 kbp. A physical map was constructed using three restriction endonucleases. A copy number of this plasmid was estimated to be 7–13 per cell. The homologous sequence was not found in the chromosomal DNA of the host cell.