Impact of Acute Metal Stress in Saccharomyces cerevisiae

Abstract

Although considered as essential cofactors for a variety of enzymatic reactions and for important structural and functional roles in cell metabolism, metals at high concentrations are potent toxic pollutants and pose complex biochemical problems for cells. We report results of single dose acute toxicity testing in the model organism S. cerevisiae. The effects of moderate toxic concentrations of 10 different human health relevant metals, Ag+, Al3+, As3+, Cd2+, Co2+, Hg2+, Mn2+, Ni2+, V3+, and Zn2+, following short-term exposure were analyzed by transcription profiling to provide the identification of early-on target genes or pathways. In contrast to common acute toxicity tests where defined endpoints are monitored we focused on the entire genomic response. We provide evidence that the induction of central elements of the oxidative stress response by the majority of investigated metals is the basic detoxification process against short-term metal exposure. General detoxification mechanisms also comprised the induction of genes coding for chaperones and those for chelation of metal ions via siderophores and amino acids. Hierarchical clustering, transcription factor analyses, and gene ontology data further revealed activation of genes involved in metal-specific protein catabolism along with repression of growth-related processes such as protein synthesis. Metal ion group specific differences in the expression responses with shared transcriptional regulators for both, up-regulation and repression were also observed. Additionally, some processes unique for individual metals were evident as well. In view of current concerns regarding environmental pollution our results may support ongoing attempts to develop methods to monitor potentially hazardous areas or liquids and to establish standardized tests using suitable eukaryotic a model organism.

The major facilitator superfamily transporter Knq1p modulates boron homeostasis in Kluyveromyces lactis

“…So, with fewer paralogs than S. cerevisiae have, K. lactis proteins may have a broader role in responding to different stress signals, whereas the WGD promoted functional specialization in S. cerevisiae. Our results corroborate also that of Hosiner et al (2014) providing evidence that the induction of central elements of the oxidative stress response by the majority of metals and metalloids is the basic detoxification process against short-term metal exposure. According to the recent data (Tamás et al 2014), heavy metals and metalloids interfere also with folding of nascent or non-native proteins in the cell, thus affecting protein homeostasis and cell viability.…”

Common and metal-specific proteomic responses to cadmium and zinc in the metal tolerant ericoid mycorrhizal fungus Oidiodendron maius Zn

“…43 In particular, 2-DE analysis of proteins secreted by the plant pathogen Botrytis cinerea in response to different metals indicated that cadmium induces a secretome signature significantly different from those induced by zinc, copper or nickel. 44 Proteins involved in these two pathways were not found in O. maius Zn, which may be either explained by the low protein coverage or by the fact that metal exposure was much longer in our experiments (30 days). 44 Proteins involved in these two pathways were not found in O. maius Zn, which may be either explained by the low protein coverage or by the fact that metal exposure was much longer in our experiments (30 days).…”

Gradual Accumulation of Heavy Metals in an Industrial Wheat Crop from Uranium Mine Soil and the Potential Use of the Herbage

“…Cd and Cu toxicities could lead to productivity losses in the fermentation of alcohol by S. cerevisiae. With that said, a higher Mn, Ni, Pb, and Zn load would be tolerated by the yeasts [57,58] and accepted by forage hygiene guidelines (Table 1 legend). Therefore, the straw did not lose its applicability as a roughage supplement in husbandry and as bioethanol feedstock if its As, Mn, Pb, and U content would essentially increase.…”

“…Baker's yeast (Saccharomyces cerevisiae) as the preferred ethanologenic organism experienced 5% and EC50 growth inhibition in solution at 0.11 and 1.12 mg·L −1 , respectively, in Cd; 55 and 96 mg·L −1 , respectively, in Mn; 59 and 117 mg·L −1 , respectively, in Ni; and 65 and 163 mg·L −1 , respectively, in Zn during 12 h of incubation [57]. The yeast exposed to 10 mg·L −1 Cd was temporarily inhibited to regain an almost normal growth rate [120] apparently owing to its biosorption capacity in the order of 45 mg Cd 2+ per gram of biomass within 2 h [121].…”