## Abstract A screening procedure based on the formation of lactoseโfermenting papillae on lactoseโnonfermenting bacterial colonies has been described. Due to supplementation of 50 ฮผg/ml 2โaminopurine in EMB plates the frequency of papillae rose to an average number of 28 papillae per colony. Of 15
A mild method for the isolation of folded chromosomes from Escherichia coli
โ Scribed by Dr. P. Dworsky
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 673 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0233-111X
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โฆ Synopsis
Abstract
Until now it has not been possible to obtain nuclear bodies from Escherichia coli after treatment with rifampicin. It was generally assumed that the crossโconnections between the DNA double strands which are sensitive towards ribonuclease are destroyed under the influence of inhibitors of RNA synthesis like rifampicin. In this paper a new lysis procedure is described for preparing nuclear bodies from E. coli. These particles differ in some respects, especially in salt sensitivity from those prepared by earlier methods. Using the new lysis method it is also possible to obtain folded chromosomes from cells after treatment with rifampicin. These nuclear bodies can be destroyed by ribonuclease. Therefore, it has to be postulated that a fraction of RNA being sufficient to hold the chromosome in the folded shape is not susceptible to the action of rifampicin.
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