Mikroskopischer Vergleich der Zellvermehrung bei Hefestämmen verschiedenen Ploidiegrades nach UV- und Peroxyd-Inaktivierung

Abstract
The microscopical pattern of rest-budding in UV or peroxide treated yeast cells was studied in strains of different ploidy. UV-irradiation caused in all investigated strains a very similar pattern, i.e. by a given effective dose, measured by the macroscopical survivals, approximately the same final frequencies of more than one and also of more than three cells in a clone could be observed in all investigated strains. It seems possible to explain these results by a non-strain-depending dose reduction factor of 2.2: 1 for the frequency of more than one cell, and 1.2: 1 for the frequency of more than three cells, both related to the commonly used macroscopical survival frequency curve. The dose reduction by photoreactivation was approximately 2: 1 and caused a corresponding shift of the microscopical pattern. After treatment with organic peroxides the microscopical pattern in haploid strains was very similar to that after UV-treatment, although there was no photoreactivation. In diploid strains there is a characteristical different pattern with nearly none rest-budding even in a strain produced by self-diploidization. These results are discussed in their bearing on possible inactivation mechanisms

This publication has 3 references indexed in Scilit: