Survival of diploid yeast cells to bleomycin in combination with UV-light or hyperthermia

• Published in: Radiation and environmental biophysics Vol. 30; no. 2; pp. 139 - 145
• Main Authors: Barrios, E, Candreva, E C, Nunes, E
• Format: Journal Article
• Language: English
• Published: Germany 01-01-1991
• Subjects: Bleomycin - pharmacology; Diploidy; Dose-Response Relationship, Drug; Dose-Response Relationship, Radiation; Hot Temperature; Saccharomyces cerevisiae; Saccharomyces cerevisiae - drug effects; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - radiation effects; Ultraviolet Rays
• ISSN: 0301-634X; 1432-2099
• DOI: 10.1007/BF01219348

In the present work we have investigated the possible interaction between Bleomycin (B) and UV light or hyperthermia (HT) in the induction of lethal events in diploid yeast populations in the stationary phase of growth. UV and B acting as single agents determine sigmoid survival curves. The combination of UV + B produces different degrees of sensitization depending on dose ranges. For [B] = 7.5 micrograms/ml combined with different UV fluences an exponential course is observed, suggesting overlapping lesion specificity of the involved repair pathways (excision and recombination). The hyperthermia plus Bleomycin treatment produces different degrees of inactivation depending on the sequences. Maximal inactivation effect was obtained for the sequence B + HT. In the case of HT + B ([B] greater than 7.5 micrograms/ml) the obtained sensitization is lower.