The aim of this study was to compare cell response of DNA deficient and proficient genotypes of Chlamydomonas reinhardtii to cadmium induced stress. Two DNA repair deficient strains (UVS-10, recombination-repair deficient and UVS-14, mismatch-repair deficient) and two DNA repair proficient strains (137C, wild type and CW15, cell-wall-less) were used. Different endpoints were applied: macro-colonies survival assay, biochemical - malondialdehyde (MDA), H2O2 and carotenoids content, and molecular - double-strand DNA breaks (DSBs) induction. The highest decreasing of cell survival for mismatchrepair deficient genotype was found after cadmium treatment. Both DNA repair deficient genotypes manifested the highest levels of DSBs induced by cadmium. Pronounced oxidative stress measured as elevated MDA, H2O2 and carotenoids content was observed in the mismatch-repair deficient genotype. Our results showed that DNA repair deficient genotypes are more susceptible to cadmium induced oxidative stress compared to DNA repair proficient genotypes.
Key words: cadmium, oxidative stress, Chlamydomonas , genotype susceptibility
Topic: BIOLOGY