Folia Microbiologica

, Volume 12, Issue 4, pp 316–322 | Cite as

Role of deoxyribonuclease in genetic transformation

II. RNA as an inhibitor of deoxyribonuclease activity in Pneumococcal strains
  • M. Kohoutová


It was found that an inhibition of the relatively low deoxyribonuclease activity in the highly transformable and stable Pneumococcus R6bd strain results in a decrease of transformation frequency. The opposite is true about the Pneumococcus PMSII57 strain where an inhibition of its high deoxyribonuclease activity results in an increase of transformation frequency. It was observed that ribonucleic acid and especially t-RNA inhibits deoxyribonuclease activity in pneumococcus strains. Hence the kinetics of the effect of t-RNA as a function of time was examined with respect to the frequency of transformants in recipient cells of R6bd strain. It was found that t-RNA inhibits transformation. Maximum inhibition occurs if t-RNA is added to the DNA-bacterial complex at the time of penetration of transforming DNA into recipient cells. The results indicate that in a highly transformable and stable Pneumococcus strain the penetration of DNA is associated with the regulation of optimal deoxyribonuclease activity.


Ribonucleic Acid Recipient Cell Transformable Strain DNase Activity Deoxyribonuclease 
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Copyright information

© Institute of Microbiology, Academy of Sciences of the Czech Republic 1967

Authors and Affiliations

  • M. Kohoutová
    • 1
  1. 1.Department of Bacterial Genetics, Institute of MicrobiologyCzechoslovak Academy of SciencesPrague 4

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