scholarly journals Cadmium-induced differential accumulation of metallothionein isoforms in the Antarctic icefish, which exhibits no basal metallothionein protein but high endogenous mRNA levels

1998 ◽  
Vol 332 (2) ◽  
pp. 475-481 ◽  
Author(s):  
Vincenzo CARGINALE ◽  
Rosaria SCUDIERO ◽  
Clemente CAPASSO ◽  
Antonio CAPASSO ◽  
Peter KILLE ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Mrna Levels ◽  
Protein Sequence Analysis ◽  
Treated Fish ◽  
Genes Encoding ◽  
Antarctic Icefish ◽  
The Antarctic ◽  
Cadmium Salt

Reverse transcriptase-mediated PCR has been used to isolate two distinct metallothionein (MT) cDNA species from RNA extracted from icefish liver, namely MT-I and MT-II. Northern blot analysis with these cDNA species revealed that significant endogenous levels of MT mRNA were present in liver tissues of normal animals despite the fact that no MT protein could be found accumulating in the same tissue. However, multiple injections of CdCl2 induced high levels of both MT mRNA and MT protein. Sequence analysis of the cDNA species that were present after cadmium injection revealed the presence of both isoforms. Quantification of the MT-I and MT-II transcripts from normal and heavy-metal-treated fish showed an alteration in the ratio of the MT isoform transcripts. Endogenous transcripts consisted mostly of MT-II, whereas the MT-I transcript was preferentially accumulated only in response to the cadmium salt. The protein encoded by each cDNA isoform was isolated from the heavy-metal-treated fish and the availability of the specific MT mRNA for translation was demonstrated by translation in vitro. These results show that: (1) there is a discrepancy between the significant endogenous levels of MT mRNA and the absence of MT protein; (2) the accumulation of MT in icefish liver can be triggered by heavy metals; (3) genes encoding distinct MT isoforms are differentially regulated by heavy metals.

scholarly journals In vivo and in vitro studies on heavy metal tolerance in Sesbania grandiflora L

2009 ◽  
Vol 3 (2) ◽  
pp. 48-64
Author(s):  
Kadhim M. Ibrahim ◽  
Shaimaa A. Yousir
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Tolerance ◽  
Heavy Metal Tolerance ◽  
Heavy Metal Concentration ◽  
Callus Cultures ◽  
Metal Levels ◽  
Whole Plants

Several experiments were carried out to study heavy metal tolerance in tissue cultures or whole plants of S. grandiflora., Callus was induced and maintained on modified Murashige and Skoog, 1962 medium (MS) supplemented with (0.5)mg/l benzyl adenine and (2)mg/l 2,4-phenoxy acetic acid . Heavy metals (Cd, Co, Cu, Cr or Zn) were added to the culture medium at different concentrations as contamination agents. In order to asses the effect of these heavy metals on seed germination; seeds were sown in soil contaminated with different concentrations of heavy metals for 3 weeks. Atomic Absorption Spectrophotometer was used for analysis of samples taken from whole plants and callus cultures. Results showed that callus fresh weight decreased with increasing heavy metal concentration in cultural medium. Germination percentages and plant heights increased over time. However, a reduction occurred in these parameters with increasing heavy metal levels. Percentages of metals accumulated in calli were (0.001, 0.011, 0.012 and 0.013%) at (0.0, 0.05, 0.075 and 0.1)mg/l Cd respectively; (0.001, 0.008, 0.016 and 0.006%) at (0.0, 0.1, 0.25 and 0.5)mg/l Co respectively; (0.001, 0.020, 0.034 and 0.015%) at (0.0, 0.075, 0.2 and 0.5)mg/l Cu respectively; (0.001, 0.013, 0.012 and 0.010%) at (0.0, 0.25, 0.4 and 0.5)mg/l Cr respectively and (0.027, 0.051, 0.059 and 0.056%) at (0.0 , 0.75, 1.0 and 1.5)mg/l Zn respectively. Percentages of metals accumulated in whole plants were (0.08, 0.55, 1.11, 0.83 and 0.44%) at (0.0, 1.0, 2.0, 3.0 and 4.0)mg/Kg soil Cd respectively; (0.11, 0.22, 0.55, 0.47 and 0.44%) at (0.0, 15.0, 30.0 45.0 and 60.0)mg/Kg soil Co respectively; (0.01, 0.10, 0.57, 0.58 and 0.72%) at (0.0, 25.0, 50.0, 75.0 and 100.0)mg/Kg soil Cu respectively. (0.08, 0.80, 1.28, 1.31 and 0.88%) at (0.0, 25.0, 50.0, 75.0 and 100.0)mg/Kg soil Cr respectively and (0.06, 1.11, 1.20, 1.83 and 2.22%) at (0.0, 100.0, 200.0, 300.0 and 400.0)mg/Kg soil Zn respectively.

scholarly journals A Review on in vitro and in vivo Bioremediation Potential of Environmental and Probiotic Species of Bacillus and other Probiotic Microorganisms for Two Heavy Metals, Cadmium and Nickel

2019 ◽  
Vol 16 (1) ◽  
pp. 01-13 ◽  
Author(s):  
Pragya Goyal ◽  
Pranoti Belapurkar ◽  
Anand Kar
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Industrial Effluents ◽  
Eukaryotic Cell ◽  
Genus Bacillus ◽  
Form Of Life ◽  
Heavy Metal Remediation ◽  
Remediation Strategies

Microbial assisted remediation is the ray of hope in the current scenario of tremendous heavy metal pollution. The indiscriminate release of heavy metal laden industrial effluents in the water bodies and soil is now manifesting itself in the form of life threatening health hazards to humans. The conventional heavy metal remediation strategies are not only expensive but are ineffective in low metal concentrations. Microbial assisted remediation of heavy metals has come forward as the cheap and easy alternative. Amongst the various bacterial genera actively involved in bioremediation of cadmium and nickel in the environment, genus Bacillus has shown remarkable ability in this respect owing to its various biochemical and genetic pathways. It can perform bioremediation using multiple mechanisms including biosorption and bioaccumulation. This genus has also been able to reduce toxicity caused by cadmium and nickel in eukaryotic cell lines and in mice, a property also found in probiotic genera like Lactobacillus and Bifidobacterium. This paper reviews the role of environmentally present and known probiotic species of genus Bacillus along with different probiotic genera for their various mechanisms involved for remediation of cadmium and nickel.

scholarly journals Draft Genome Sequence of the Novel Enterobacter cloacae Strain amazonensis, a Highly Heavy Metal-Resistant Bacterium from a Contaminated Stream in Amazonas, Brazil

2018 ◽  
Vol 6 (22) ◽  
Author(s):  
Maria Clara Tavares Astolfi ◽  
Elen Bethleen de Souza Carvalho ◽  
Adriane Menezes de Barros ◽  
Marcelo Valente Pinto ◽  
Luna Barrôco de Lacerda ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Draft Genome ◽  
Enterobacter Cloacae ◽  
The Novel ◽  
Biotechnological Applications ◽  
Toxic Compounds ◽  
Content Type ◽  
Genes Encoding ◽  
Heavy Metal Resistant

ABSTRACT Here, we report the draft genome of the Enterobacter cloacae strain amazonensis, a bacterium highly resistant to mercury that was isolated from a metal- and sewage-contaminated stream in Amazonas, Brazil. The exploration of the 5.0-Mb genome revealed 104 genes encoding resistance to toxic compounds and heavy metals, highlighting the potential biotechnological applications of this strain.

scholarly journals Excystation of Eimeria tenella Sporozoites Impaired by Antibody Recognizing Gametocyte/Oocyst Antigens GAM22 and GAM56

2007 ◽  
Vol 7 (2) ◽  
pp. 202-211 ◽  
Author(s):  
Jürgen Krücken ◽  
Ralf J. Hosse ◽  
Aimdip N. Mouafo ◽  
Rolf Entzeroth ◽  
Stefan Bierbaum ◽  
...  
Keyword(s):  
Phage Display Library ◽  
Northern Blotting ◽  
Eimeria Tenella ◽  
Genome Project ◽  
The Novel ◽  
Protein Sequence Analysis ◽  
Oocyst Wall ◽  
Body Type ◽  
Genes Encoding

ABSTRACT Eimeria tenella is the causative agent of coccidiosis in poultry. Infection of the chicken intestine begins with ingestion of sporulated oocysts releasing sporocysts, which in turn release invasive sporozoites. The monoclonal antibody E2E5 recognizes wall-forming body type II (WFBII) in gametocytes and the WFBII-derived inner wall of oocysts. Here we describe that this antibody also binds to the stieda body of sporocysts and significantly impairs in vitro excystation of sporozoites. Using affinity chromatography and protein sequence analysis, E2E5 is shown to recognize EtGAM56, the E. tenella ortholog of the Eimeria maxima gametocyte-specific GAM56 protein. In addition, this antibody was used to screen a genomic phage display library presenting E. tenella antigens as fusion proteins with the gene VIII product on the surfaces of phagemid particles and identified the novel 22-kDa histidine- and proline-rich protein EtGAM22. The Etgam22 mRNA is expressed predominantly at the gametocyte stage, as detected by Northern blotting. Southern blot analysis in combination with data from the E. tenella genome project revealed that Etgam22 is an intronless multicopy gene, with approximately 12 to 22 copies in head-to-tail arrangement. Conspicuously, Etgam56 is also intronless and is localized adjacent to another gam56-like gene, Etgam59. Our data suggest that amplification is common for genes encoding oocyst wall proteins.

scholarly journals Engineering Forest Trees with Heavy Metal Resistance Genes

2006 ◽  
Vol 55 (1-6) ◽  
pp. 263-268 ◽  
Author(s):  
Scott A. Merkle
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Field Tests ◽  
Environmentally Friendly ◽  
Woody Species ◽  
Metal Resistance ◽  
Transgenic Trees ◽  
Forest Trees ◽  
Toxic Heavy Metals

Abstract Pollution of soil and water with heavy metals such as mercury, cadmium and arsenic, is a worldwide problem. Phytoremediation, the use of plants to remove, sequester or detoxify pollutants, including heavy metals, offers an environmentally-friendly alternative to engineering- based methods for remediation. Forest trees have multiple features that make them particularly useful for removal of toxic heavy metals, especially if they can be engineered with genes allowing them to handle high levels of these elements. Although still in its infancy, research with transgenic trees carrying genes allowing them to detoxify or sequester some heavy metals has already made promising progress. Most of the work to date has been performed using poplar species and hybrids, although other woody species could be equally as useful. Trees have been engineered with genes for the handling of mercury, cadmium, copper and arsenic following two main approaches, phytoextraction and phytotransformation/ phytovolatilizaton. In vitro studies have shown the transgenic trees to have enhanced abilities to tolerate and/or accumulate these metals, and preliminary results from field tests indicate that the trees are functioning. New combinations of genes involved in metal transport or conversion may further enhance the heavy metal remediation capabilities of the transgenic trees. Given the environmentally friendly application, forest trees engineered for phytoremediation may be some of the first transgenic forest trees approved for operational deployment.

scholarly journals Gene Expression Analysis of the Streptococcus pneumoniae Competence Regulons by Use of DNA Microarrays

2000 ◽  
Vol 182 (21) ◽  
pp. 6192-6202 ◽  
Author(s):  
Scott Peterson ◽  
Robin T. Cline ◽  
Hervé Tettelin ◽  
Vasily Sharov ◽  
Donald A. Morrison
Keyword(s):  
Streptococcus Pneumoniae ◽  
Dna Microarrays ◽  
Target Genes ◽  
Expression Patterns ◽  
In Vitro Models ◽  
Regulatory Genes ◽  
Mrna Levels ◽  
Similar Expression Pattern ◽  
Genes Encoding

ABSTRACT Competence for genetic transformation in Streptococcus pneumoniae is coordinated by the competence-stimulating peptide (CSP), which induces a sudden and transient appearance of competence during exponential growth in vitro. Models of this quorum-sensing mechanism have proposed sequential expression of several regulatory genes followed by induction of target genes encoding DNA-processing-pathway proteins. Although many genes required for transformation are known to be expressed only in response to CSP, the relative timing of their expression has not been established. Overlapping expression patterns for the genes cinA andcomD (G. Alloing, B. Martin, C. Granadel, and J. P. Claverys, Mol. Microbiol. 29:75–83, 1998) suggest that at least two distinct regulatory mechanisms may underlie the competence cycle. DNA microarrays were used to estimate mRNA levels for all known competence operons during induction of competence by CSP. The known competence regulatory operons, comAB, comCDE, andcomX, exhibited a low or zero initial (uninduced) signal, strongly increased expression during the period between 5 and 12 min after CSP addition, and a decrease nearly to original values by 15 min after initiation of exposure to CSP. The remaining competence genes displayed a similar expression pattern, but with an additional delay of approximately 5 min. In a mutant defective in ComX, which may act as an alternate sigma factor to allow expression of the target competence genes, the same regulatory genes were induced, but the other competence genes were not. Finally, examination of the expression of 60 candidate sites not previously associated with competence identified eight additional loci that could be induced by CSP.

scholarly journals Wnt/β-Catenin and Wnt5a/Ca2+ Pathways Regulate Proliferation and Apoptosis of Keratinocytes in Psoriasis Lesions

2015 ◽  
Vol 36 (5) ◽  
pp. 1890-1902 ◽  
Author(s):  
Yanfei Zhang ◽  
Chen Tu ◽  
Dingwei Zhang ◽  
Yan Zheng ◽  
Zhenhui Peng ◽  
...  
Keyword(s):  
Human Keratinocytes ◽  
Mrna Levels ◽  
Protein Levels ◽  
Proliferation And Apoptosis ◽  
Genes Encoding ◽  
Keratinocyte Cell ◽  
Normal Human ◽  
Induced Apoptosis ◽  
Psoriatic Lesions

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.

scholarly journals BIOAVAILABLE FORMS OF HEAVY METALS FROM RICE SAMPLES AND ITS POTENTIAL HEALTH RISK ASSESSMENT

2021 ◽  
Vol 9 (1) ◽  
pp. 25-35
Author(s):  
Periyasamy Dhevagi ◽  
◽  
Ambikapathi Ramya ◽  
Murugaiyan Sindhuja ◽  
Sengottiyan Priyatharshini ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Heavy Metal ◽  
Health Risk ◽  
Metal Concentration ◽  
Contaminated Soils ◽  
Food Crops ◽  
Metal Analysis ◽  
Rice Samples

Food crops grown in contaminated soils have a greater accumulation of heavy metals and the consumption of food crops grown in the contaminated soils are the source of metals that enters into the human body. Rice being a major food crop, the presence of heavy metals should be monitored regularly for reducing health risk. The analysis of total heavy metal always overestimates the content which leads to misinterpretation of results; however, bioaccessible heavy metal analysis projects the actual health risk. Hence, the present study aims to assess the bioavailable form of heavy metals in rice. The rice samples were collected from 20 different places and used for the inherent and bioavailable metal estimation. In vitro simulated digestion method was applied for bioaccessible metal analysis. Metal concentration in polished rice ranged from 0.10 to 0.82, 0.10 to 1.07, 0.11 to 0.56 and 0.23 to 1.09 mg kg-1 for Lead (Pb), Nickel (Ni), Cadmium (Cd) and Chromium (Cr), respectively. Twenty five percent of the samples recorded less than 0.028, 0.01, 0.01, and 0.03 mg kg-1 of bioaccessible Pb, Ni, Cd, and Cr, respectively. A significant negative correlation was observed between total metal concentration and bioaccessibility percentage. Targeted Hazard Quotient (THQ) of all the metals were less than one for adults indicating that there were no health risks, which undoubtedly reveals the importance of bioaccessible metal analysis. Hence, regular monitoring of heavy metals is essential to reduce the intensive accumulation in the human food chain. Also, the present study has opened up a wide scope on human health risk assessment using an in vitro digestion model.

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