HSF1 mediated stress response of heavy metals

Two Burkholderia spp. (strains SRS-25 and SRS-46) were isolated from high concentrations of uranium (U) from the U.S. Department of Energy (DOE)-managed Savannah River Site (SRS). SRS contains soil gradients that remain co-contaminated by heavy metals from previous nuclear weapons production activities. Uranium (U) is one of the dominant contaminants within the SRS impacted soils, which can be microbially transformed into less toxic forms. We established microcosms containing strains SRS-25 and SRS-46 spiked with U and evaluated the microbially-mediated depletion with concomitant genomic and proteomic analysis. Both strains showed a rapid depletion of U; draft genome sequences revealed SRS-25 genome to be of approximately 8,152,324 bp, a G + C content of 66.5, containing a total 7604 coding sequences with 77 total RNA genes. Similarly, strain SRS-46 contained a genome size of 8,587,429 bp with a G + C content of 67.1, 7895 coding sequences, with 73 total RNA genes, respectively. An in-depth, genome-wide comparisons between strains 25, 46 and a previously isolated strain from our research (Burkholderia sp. strain SRS-W-2-2016), revealed a common pool of 3128 genes; many were found to be homologues to previously characterized metal resistance genes (e.g., for cadmium, cobalt, and zinc), as well as for transporter, stress/detoxification, cytochromes, and drug resistance functions. Furthermore, proteomic analysis of strains with or without U stress, revealed the increased expression of 34 proteins from strain SRS-25 and 52 proteins from strain SRS-46; similar to the genomic analyses, many of these proteins have previously been shown to function in stress response, DNA repair, protein biosynthesis and metabolism. Overall, this comparative proteogenomics study confirms the repertoire of metabolic and stress response functions likely rendering the ecological competitiveness to the isolated strains for colonization and survival in the heavy metals contaminated SRS soil habitat.

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Corticosteroid Concentrations in Sockeye Salmon (Oncorhynchus nerka) Exposed to Low Concentrations of Copper

Journal of the Fisheries Research Board of Canada ◽

10.1139/f75-065 ◽

1975 ◽

Vol 32 (4) ◽

pp. 533-539 ◽

Cited By ~ 73

Author(s):

Edward M. Donaldson ◽

Helen M. Dye

Keyword(s):

Heavy Metals ◽

Stress Response ◽

Plasma Cortisol ◽

Sockeye Salmon ◽

Oncorhynchus Nerka ◽

Rapid Evaluation ◽

Low Concentrations ◽

Competitive Protein Binding ◽

Cupric Sulphate ◽

Sublethal Concentrations

Yearling sockeye salmon (Oncorhynchus nerka) were exposed for 1–24 h to 10−7, 10−6, or 10−5 molar cupric sulphate in freshwater aquaria. Plasma cortisol, cortisone, and "total" corticosteroid concentrations were measured by a competitive protein binding technique.Cortisol, cortisone and "total" corticosteroid levels were significantly higher than control concentrations after 1 h of exposure to 10−5 or 10−6 M copper. "Total" corticosteroid and cortisone concentrations were significantly higher than control concentrations after 2 and 4 h of exposure to 10−7 M copper, respectively. Fish exposed to 10−5 M copper died between 8 and 24 h.The data reflect a rapid corticosteroid stress response to lethal and sublethal concentrations of copper. The technique may be of use for rapid evaluation of effluents containing heavy metals, especially those containing a mixture of toxicants.

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Toksisitas Merkuri (Hg) pada struktur jaringan ikan

e-Journal BUDIDAYA PERAIRAN ◽

10.35800/bdp.9.1.2021.31565 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Tamrin A. Ibrahim ◽

Muhammad Aris

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Immune System ◽

Stress Response ◽

Experimental Research ◽

Food Chain ◽

The Body ◽

Tissue Structure ◽

Industrial Activities ◽

Conducting Research

The problem of pollution that occurs in the aquatic environment is getting out of control and causes the degradation of fishery resources which are important for humans. One of the pollutants from industrial activities is heavy metal. There are various kinds of heavy metals, mercury (Hg) is the most dangerous heavy metal. Mercury (Hg) enters directly into the waters through rainwater and leaching the soil and river flows which are then absorbed and metabolized by microorganisms. Mercury (Hg) is difficult to degrade from the body, because mercury (Hg) is actively involved in the food chain. Microorganisms feed molluscs, crustaceans and fish which are a source of protein for humans. Mercury (Hg) toxicity in fish can result in a stress response in fish which results in impaired growth, immune system, and changes in tissue structure. This brief review aimed to enrich the scientific repertoire of the toxicity of mercury (Hg) in fish and its effects on humans. This review was a non-experimental research by conducting research around the literature

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The cssR gene of Corynebacterium glutamicum plays a negative regulatory role in stress responses

Microbial Cell Factories ◽

10.1186/s12934-021-01600-8 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Yang Liu ◽

Wenzhi Yang ◽

Tao Su ◽

Chengchuan Che ◽

Guizhi Li ◽

...

Keyword(s):

Heavy Metals ◽

Stress Response ◽

Corynebacterium Glutamicum ◽

Conformational Changes ◽

Stress Responses ◽

Redox Homeostasis ◽

Redox Activity ◽

Cysteine Residues ◽

Gene Promoters ◽

Wide Range

Abstract Background CssR, the product of the Corynebacterium glutamicum ncgl1578 gene cotranscribed with ncgl1579, is a TetR (tetracycline regulator) family repressor. Although many TetR-type regulators in C. glutamicum have been extensively described, members of the TetR family involved in the stress response remain unidentified. Results In this study, we found that CssR regulated the transcription of its own gene and the ncgl1576-ncgl1577 operon. The ncgl1576-ncgl1577 operon, which is located upstream of cssR in the orientation opposite that of the cssR operon, encodes an ATP-binding cassette (ABC), some of which are involved in the export of a wide range of antimicrobial compounds. The cssR-deletion (ΔcssR) mutant displayed increased resistance to various stresses. An imperfect palindromic motif (5′-TAA(G)TGN13CA(G)TTA-3′; 25 bp) located at the intergenic region between cssR and ncgl1577 was identified as the sole binding site for CssR. Expression of cssR and ncgl1577 was induced by antibiotics and heavy metals but not H2O2 or diamide, and the DNA-binding activity of CssR was impaired by antibiotics and heavy metals but not H2O2. Antibiotics and heavy metals caused CssR dissociation from target gene promoters, thus derepressing their transcription. Oxidant treatment neither altered the conformation of CssR nor modified its cysteine residues, indicating that the cysteine residues in CssR have no redox activity. In the ΔcssR mutant strain, genes involved in redox homeostasis also showed increased transcription levels, and the NADPH/NADP+ ratio was higher than that of the parental strain. Conclusion The stress response mechanism of CssR in C. glutamicum is realized via ligand-induced conformational changes of the protein, not via cysteine oxidation-based thiol modification. Moreover, the crucial role of CssR in the stress response was demonstrated by negatively controlling the expression of the ncgl1576-ncgl1577 operon, its structural gene, and/or redox homeostasis-related genes.

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Gene Determinants for Mercury Bioremediation as Revealed by Draft Genome Sequence Analysis of Stenotrophomonas sp. Strain MA5

Microbiology Resource Announcements ◽

10.1128/mra.00130-19 ◽

2019 ◽

Vol 8 (17) ◽

Cited By ~ 3

Author(s):

Ashish Pathak ◽

Meenakshi Agarwal ◽

Rajesh Singh Rathore ◽

Ashvini Chauhan

Keyword(s):

Heavy Metals ◽

Stress Response ◽

Sequence Analysis ◽

Genome Sequence ◽

Contaminated Soil ◽

Draft Genome ◽

Draft Genome Sequence ◽

Multidrug Efflux ◽

Genome Sequence Analysis ◽

Cellular Survival

A soilborne Stenotrophomonas sp. strain (MA5) that is resistant to mercury was isolated. A draft genome sequence-based analysis revealed a suite of gene determinants to resist mercury and other heavy metals, multidrug efflux, stress response, and membrane transport, and these provide cues to a suite of mechanisms that underpin cellular survival in contaminated soil.

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Impaired cortisol secretion in yellow perch (Perca flavescens) from lakes contaminated by heavy metals: in vivo and in vitro assessment

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-200 ◽

1997 ◽

Vol 54 (12) ◽

pp. 2752-2758 ◽

Cited By ~ 52

Author(s):

Julie C Brodeur ◽

Graham Sherwood ◽

Joseph B Rasmussen ◽

Alice Hontela

Keyword(s):

Heavy Metals ◽

Stress Response ◽

Plasma Cortisol ◽

Yellow Perch ◽

Acute Stress ◽

Perca Flavescens ◽

Contaminated Site ◽

Cortisol Levels

The characteristic elevation of plasma cortisol levels in response to an acute stress of capture was impaired in both male and female yellow perch (Perca flavescens) from lakes contaminated by heavy metals. The impairment of the cortisol stress response was observed in fish 4 + years and older whereas the capacity to elevate plasma cortisol levels of fish younger than 4 + was not significantly different at contaminated and reference sites. The responsiveness to ACTH of the interrenal tissue of 4 + yellow perch was evalutated in vitro to determine whether the impairment of the cortisol stress response is caused by a dysfunction of the interrenal tissue or if the dysfunction is located elsewhere in the hypothalamo-pituitary-interrenal axis controlling the secretion of cortisol. The amount of cortisol secreted by the interrenal tissue of yellow perch from a contaminated site in response to a 10-min stimulation with 10-7 M ACTH was significantly lower compared with fish from the reference site. These results indicate that the impairment of the cortisol stress response observed in fish from polluted sites is caused, at least in part, by a dysfunction of the interrenal tissue.

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Short- and Long-Term Exposure to Heavy Metals Induced Oxidative Stress Response inPseudokirchneriellasubcapitata

CLEAN - Soil Air Water ◽

10.1002/clen.201600020 ◽

2016 ◽

Vol 44 (11) ◽

pp. 1578-1583 ◽

Cited By ~ 11

Author(s):

Manuela D. Machado ◽

Eduardo V. Soares

Keyword(s):

Oxidative Stress ◽

Heavy Metals ◽

Stress Response ◽

Oxidative Stress Response ◽

Short And Long Term

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Genome-wide association study reveals complex genetic architecture of cadmium and mercury accumulation and tolerance traits in Medicago truncatula

10.1101/2021.10.29.465169 ◽

2021 ◽

Author(s):

Tim Paape ◽

Benjamin Heiniger ◽

Miguel Santo Domingo ◽

Michael Clear ◽

M. Mercedes Lucas ◽

...

Keyword(s):

Heavy Metals ◽

Stress Response ◽

Association Study ◽

Genome Wide Association Study ◽

Genome Wide Association ◽

Stress Response Genes ◽

Genome Wide ◽

Leaf Accumulation ◽

Genomic Regions ◽

P Type

Heavy metals are an increasing problem due to contamination from human sources that and can enter the food chain by being taken up by plants. Understanding the genetic basis of accumulation and tolerance in plants is important for reducing the uptake of toxic metals in crops and crop relatives, as well as for removing heavy metals from soils by means of phytoremediation. Following exposure of Medicago truncatula seedlings to cadmium (Cd) and mercury (Hg), we conducted a genome-wide association study using relative root growth (RRG) and leaf accumulation measurements. Cd and Hg accumulation and RRG had heritability ranging 0.44 - 0.72 indicating high genetic diversity for these traits. The Cd and Hg trait associations were broadly distributed throughout the genome, indicated the traits are polygenic and involve several quantitative loci. For all traits, candidate genes included several membrane associated ATP-binding cassette transporters, P-type ATPase transporters, several oxidative stress response genes and stress related UDP-glycosyltransferases. The P-type ATPase transporters and ATP-binding cassette protein-families have roles in vacuole transport of heavy metals, and our findings support their wide use in physiological plant responses to heavy metals and abiotic stresses. We also found associations between Cd RRG with the genes CAX3 and PDR3, two linked adjacent genes, and leaf accumulation of Hg associated with the genes NRAMP6 and CAX9. When plant genotypes with the most extreme phenotypes were compared, we found significant divergence in genomic regions using population genomics methods that contained metal transport and stress response gene ontologies. Several of these genomic regions show high linkage disequilibrium (LD) among candidate genes suggesting they have evolved together. Minor allele frequency (MAF) and effect size of the most significant SNPs was negatively correlated with large effect alleles being most rare. This is consistent with purifying selection against alleles that increase toxicity and abiotic stress. Conversely, the alleles with large affect that had higher frequencies that were associated with the exclusion of Cd and Hg. Overall, macroevolutionary conservation of heavy metal and stress response genes is important for improvement of forage crops by harnessing wild genetic variants in gene banks such as the Medicago HapMap collection.

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Kontaminasi logam nikel (Ni) pada struktur jaringan ikan

e-Journal BUDIDAYA PERAIRAN ◽

10.35800/bdp.9.1.2021.31566 ◽

2020 ◽

Vol 9 (1) ◽

Author(s):

Muhammad Aris ◽

Tamrin A. Ibrahim ◽

Lidiawati Nasir

Keyword(s):

Heavy Metals ◽

Immune System ◽

Stress Response ◽

Metal Contamination ◽

Soil Washing ◽

Mining Industry ◽

Tissue Structure ◽

Nickel Metal ◽

Industrial Activities ◽

Conducting Research

The development and progress in the mining industry has created an opportunity for the concentration of heavy metals to increase uncontrolled in waters and lead to degradation of fishery resources. Heavy metals are one of the pollutants from industrial activities that enter directly into the waters through rainwater and soil washing and river flows which are then absorbed and metabolized by microorganisms. Heavy metals are difficult to degrade and are actively involved in the food chain. Microorganisms feed molluscs, crustaceans and fish which are a source of protein for humans. Nickel metal (Ni) is a metal that can cause a stress response in fish which results in impaired growth, immune system, and changes in tissue structure. This brief review aims to enrich the scientific repertoire of nickel (Ni) metal contamination in fish and its impact on humans. This review is a non-experimental research by conducting research around the literature

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