Isolation and characterization of yeast mutants with thermoconditional sensitivity to the bifunctional alkylating agent nitrogen mustard

✍ Scribed by Wolfram Siede; Martin Brendel

• Publisher: Springer-Verlag
• Year: 1981
• Tongue: English
• Weight: 479 KB
• Volume: 4
• Category: Article
• ISSN: 0172-8083
• DOI: 10.1007/bf00365693

✦ Synopsis

Selection of mutants of Saccharomyces cerevisiae sensitive to the DNA cross-linking agent nitrogen mustard (HN2) at two temperatures (23 °C and 36 °C) yielded two isolates with thermoconditionally enhanced (ts) sensitivity to the mutagen. Both were due to single recessive nuclear genes. Mutant allele snml-2 ts showed mainly ts-sensitivity to HN2, whereas mutant allele snm2-1 ts conferred ts-sensitivity to HN2, half mustard (HN1) and UV. In temperature-shift experiments it was determined that the functions of SNM1 and SNM2 are needed for recovery within 6 to 7 h. after mutagen exposure during incubation at 23 °C on YEPD when HN2 and UV are applied. After HN1 treatment the SNM2 coded function is required for recovery for about 14 hrs. This possibly indicates a handling of UV-und HN2-induced lesions different from that of HN 1-induced lesions.