Die mutagene Wirkung einiger Radiomimetika auf den Coliphagen T 2

Pathobiology ◽  
1963 ◽  
Vol 26 (2) ◽  
pp. 237-249
Author(s):  
L. Degen
Keyword(s):  
Mutagene Wirkung

Untersuchungen �ber die mutagene Wirkung einiger Cytostatica

1958 ◽  
Vol 62 (3) ◽  
pp. 347-355 ◽  
Author(s):  
H. Henke ◽  
G. H�hne ◽  
H. A. K�nkel
Keyword(s):  
Mutagene Wirkung

Die mutagene Wirkung von Trenimon bei der m�nnlichen Maus

1965 ◽  
Vol 1 (6) ◽  
pp. 576-578 ◽  
Author(s):  
Gunter R�hrborn
Keyword(s):  
Mutagene Wirkung

Mutagene Wirkung von Hydrazin auf Escherichia coli-Zellen

1961 ◽  
Vol 48 (13) ◽  
pp. 480-480 ◽  
Author(s):  
Franz Lingens
Keyword(s):  
Escherichia Coli ◽  
Mutagene Wirkung

Inaktivierende und mutagene Wirkung salpetriger Säure auf Zellen von Escherichia coli

1959 ◽  
Vol 14 (8-9) ◽  
pp. 528-537 ◽  
Author(s):  
F. Kaudewitz
Keyword(s):  
Escherichia Coli ◽  
Nitrous Acid ◽  
Single Cells ◽  
Wild Type ◽  
Inactivation Curve ◽  
E Coli ◽  
Auxotrophic Mutants ◽  
Induced Mutants ◽  
Mutagene Wirkung ◽  
Cellular Dna

Cells of E. coli B incubated with NaNO2 undergo inactivation. In non-metabolizing cells the inactivation follows a two hit curve. In metabolizing cells the rate of inactivation is increased and the inactivation curve does not show two-hit kinetics. The rate of inactivation decreases with rising pH and decreasing NaNO2-concentration. Therefore nitrous acid appears to be the active substance.Nitrous acid proved to be a potent mutagen as shown by isolation of auxotrophic mutants. With an inactivation rate of 10-4 about 1.4 per cent of the surviving cells were auxotrophs. The probability that this increase in mutants may be due to selection during inactivation of auxotrophs present before exposure was excluded experimentally. In none of 559 auxotrophic colonies grown from single cells which had survived contact with nitrous acid wild-type sectors were found. For metabolizing and nonmetabolizing cells the increase of the percentage of auxotrophic mutants with increasing time of exposure to HNO2 followed a two-hit curve. In these experiments the percentage of induced mutants was independent of the different rate of inactivation caused by different states of metabolism and dependent only on the time of incubation with nitrous acid. The results are discussed as being in agreement with the assumption that in non-metabolizing cells nitrous acid acts directly on the cellular DNA leading to inactivation and mutation.

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