It is generally assumed that genetic research of mycobacteria is delayed as compared with other, more commonly used, bacterial models, particularly in the field of genetic transfers. In the field of mutagenesis the problems have been studied to such an extent that replication maps of the chromosome of M. phlei and M. tuberculosis H37 Rv have already been constructed and a new model of the cell cycle of bacteria exhibiting a slow growth rate has been worked out. When the problems of mycobacterial genetics are looked upon in the light of gene manipulations it may be concluded that mycobacteria belong to a few models whose genes are used for cloning and that problems of practical significance will be studied by means of the most modern approaches.

• MeSH
• mikrobiální genetika * MeSH
• Mycobacterium genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The initial replication region of the chromosome on the replication map of M. phlei constructed by means of sequential mutagenesis in synchronous populations was accurately determined. By following the time shift of the replication moment of the genes bac and met in the control culture and in the culture with the initial inhibition of DNA synthesis by nalidixic acid the start of replication of the chromosome was determined at 15 min before replication of the gene ile. On the basis of the results obtained a scheme of the cell cycle in M. phlei was proposed. Intervals C and D depend on the generation time, become prolonged independently of each other and assume the whole cycle. The ratio C/(C + D) equals to 0.56 and the interval D has a value of 0.76 of the interval C. The mutual ratio of the intervals C : D is 1.3 : 1.0. The obtained results make it possible to form the assumption about mutual ratios between the chromosome replication and cell division in bacteria exhibiting slow growth rates.

• MeSH
• bakteriální chromozomy MeSH
• buněčný cyklus MeSH
• časové faktory MeSH
• DNA bakterií biosyntéza   MeSH
• Escherichia coli cytologie   MeSH
• kyselina nalidixová farmakologie   MeSH
• Mycobacterium phlei cytologie   genetika   MeSH
• Mycobacterium cytologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DNA bakterií MeSH
• kyselina nalidixová MeSH