Possible accumulation of non-active molecules of catalase and superoxide dismutase in S. cerevisiae cells under hydrogen peroxide induced stress

Abstract

Abstract:The effect of hydrogen peroxide on the activities of catalase and superoxide dismutase (SOD) in S. cerevisiae has been studied under different experimental conditions: various H 2 O 2 concentrations, time exposures, yeast cell densities and media for stress induction. The yeast treatment with 0.25 − 0.50 mM H 2 O 2 led to an increase in catalase activity by 2 − 3-fold. At the same time, hydrogen peroxide caused an elevation by 1.6-fold or no increase in SOD activity dependently on conditions used. This effect was cancelled by cycloheximide, an inhibitor of protein synthesis in eukaryotes. Weak elevation of catalase and SOD activities in cells treated with 0.25 − 0.50 mM H 2 O 2 found in this study does not correspond to high level of synthesis of the respective enzyme molecules observed earlier by others. It is well known that exposure of microorganisms to low sublethal concentrations of hydrogen peroxide leads to the acquisition of cellular resistance to a subsequent lethal oxidative stress. Hence, it makes possible to suggest that S. cerevisiae cells treated with low sublethal doses of hydrogen peroxide accumulate nonactive stress-protectant molecules of catalase and SOD to survive further lethal oxidant concentrations.

Hydrogen peroxide-induced response in E. coli and S. cerevisiae: different stages of the flow of the genetic information

“…That is why in our experiments we investigated widely used strains obtained from other laboratoties. However, rather different results have been found by Zheng et al [18] and in our laboratory [20] with E. coli MC4100 cells using the same stress conditions as well as with S. cerevisiae YPH98 strain investigated by Godon et al [36] and us [85].…”

“…It should be noted that in the two mentioned above experiments [87,91], the strains other than S. cerevisiae YPH98 were used: single mutants of YPH250 defective in catalase T or A [87,91] and single mutants of EG103 lacking SOD1 or SOD2 [87]. However, as seen in Table 2, using the same stress conditions and the same yeast strain YPH98 which were employed by Godon with colleagues [36], we found that hydrogen peroxide only slightly increased catalase activity and did not change SOD activity [85]. Overall, our data on weak elevation of catalase and SOD do not correspond to a high level of synthesis of the respective enzyme molecules observed earlier by Godon et al [36].…”

“…Certain studies employing comparative genomic, proteomic and other approaches demonstrate a lack of correlation between either the mRNA and protein amounts of many genes or the levels and functional activities of some proteins [81][82][83][84][85]. We have analyzed the literature reported on E. coli and S. cerevisiae adaptive response to hydrogen peroxide at different stages of the flow of the genetic information: from transcription and translation to enzyme activity (Tables 1 and 2 Tables 1 and 2, various strains and experimental conditions were used in the studies.…”

“…Gene name S. cerevisiae strain was used, the changes in protein synthesis did not reflect the alteration in the activities of respective enzymes in cells exposed to oxidants [83,85]. Cyrne with colleagues found, that in stationary phase S. cerevisiae EG103 cells treated by menadione, the increases in Mn-SOD, Cu,Zn-SOD and glutathione reductase mRNA steady state levels were not paralleled by increased protein levels and enzymatic activities [83].…”

Acetate but not propionate induces oxidative stress in bakers’ yeastSaccharomyces cerevisiae

“…Earlier we suggested that cells treated with low sublethal concentrations of hydrogen peroxide accumulated non-active stress-protective molecules, further activation of which made microorganisms resistant to lethal concentrations of H 2 O 2 . 25,47 Overall, microorganism exposure to mild stress leads to the acquisition of cellular resistance to lethal stress. 5,6,[23][24][25] Here we found that H 2 O 2 pre-incubation increased the survival of yeast exposed to 200 mM AA (Fig.…”