X-Ray study of competence development in Bacillus subtilis
โ Scribed by Epstein, H. T.
- Publisher
- Springer
- Year
- 1971
- Tongue
- English
- Weight
- 264 KB
- Volume
- 110
- Category
- Article
- ISSN
- 0026-8925
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โฆ Synopsis
Bacillus subtilis were x-irradiated before and after centrifugal separation of cells in a Renografin density gradient. 1)re-competent cultures have no cells at the radiosensitivity of the cells in the bulk competent culture, but there is a substantial fraction of cells in a multi-target state, with heterogeneous target numbers. On reaching maximal competence, the survival becomes entirely linear in radiosensitivity. Irradiation of the separated competent cells shows that competence development correlates with disappearance of multi-target cells from the non-competent band of cells and the appearance of single-target cells in the competent band at a radiosensitivity equal to that of the bulk competent culture. Thus the multi-target state may be a required stage in the development of competence in this system.
๐ SIMILAR VOLUMES
Using the transformation-deficient mutant M465, which was previously isolated by means of insertional mutagenesis with plasmid pHV60, a transcription unit comL required for genetic competence of Bacillus subtilis was identified. A chromosomal DNA fragment flanking the inserted pHV60 was isolated and