Effect of copper and lead on lipid metabolism in bryophytes and lichens

2000 ◽  
Vol 28 (6) ◽  
pp. 910-912 ◽  
Author(s):  
I. A. Guschina ◽  
J. L. Harwood

Bryophytes and lichens have a widespread occurrence and can survive under extreme environmental conditions, such as drought, low temperatures, continuous light or prolonged darkness. It has been shown that lipid metabolism is sensitive to both metal response and metal resistance mechanisms in many organisms, including yeast, Silene cucubalus and in the marine brown algae Fucus spp. and Ascophyllum nodosum. In the present study, the effects of lead and copper on lipid metabolism have been studied in two moss species, Rhytidiadelphus squarrosus and Dicranum scoparium and also in the lichen Peltigera horizontalis with a cyanobacterial Nostoc photobiont.


2013 ◽  
Vol 10 (2) ◽  
pp. 2345-2375 ◽  
Author(s):  
E. Schütze ◽  
A. Weist ◽  
M. Klose ◽  
T. Wach ◽  
M. Schumann ◽  
...  

Abstract. Biomineralization by heavy metal resistant streptomycetes was tested to evaluate the potential influence on metal mobilities in soil. Thus, we designed an experiment adopting conditions from classical laboratory methods to natural conditions prevailing in metal-rich soils with media spiked with heavy metals, soil agar, and nutrient enriched or unamended soil incubated with the bacteria. As a result, all strains were able to form struvite minerals on tryptic soy broth (TSB) media supplemented with AlCl2, MnCl2 and CuSO4, as well as on soil agar. Some strains additionally formed struvite on nutrient enriched contaminated and control soil, as well as on metal contaminated soil without addition of media components. In contrast, switzerite was exclusively formed on minimal media spiked with MnCl2 by four heavy metal resistant strains, and on nutrient enriched control soil by one strain. Hydrated nickel hydrogen phosphate was only crystallized on complex media supplemented with NiSO4 by most strains. Thus, mineralization is a~dominant property of streptomycetes, with different processes likely to occur under laboratory conditions and sub-natural to natural conditions. This new understanding may be transferred to formation of minerals in rock and sediment evolution, to ore deposit formation, and also might have implications for our understanding of biological metal resistance mechanisms. We assume that biogeochemical cycles, nutrient storage and metal resistance might be affected by formation and re-solubilization of minerals like struvite in soil at microscale.



1983 ◽  
Vol 61 (9) ◽  
pp. 2384-2387
Author(s):  
Helen P. Ramsay

Chromosome numbers are reported for six moss species from western Canada, four from British Columbia, two from Alberta. These give data on chromosome numbers from new localities in Canada for populations of five species and the first record for Kiaeria starkei from Canada. Chromosome numbers reported are n = 13, Grimmia afftnis; n = 14, Kiaeria starkei; n = 14 (13 + m), Dicranum scoparium; n = 20, Bryum pseudotriquetrum; n = 11, Ptilium crista-castrensis; and n = 6, Hypnum circinale.



2007 ◽  
Vol 20-21 ◽  
pp. 362-365
Author(s):  
K. Pakshirajan

Cell surface hydropobicity plays a significant role in microbe-mineral interactions with special relevance of bioleaching. The present investigation envisages a study on the hydrophobic character of Acidiphilium symbioticum KM2, an acidophilic strain of bioleaching environment, when grown in presence of heavy metals - copper, zinc, cadmium and nickel. The metals, at its sub inhibitory concentrations (MIC50), exhibited profound negative effect on the growth of the bacterium. Inhibition on the culture growth rate was highest due to cadmium followed by zinc, nickel and copper. However, upon successive adaptation in different concentrations of each metal in ascending order, the cells could grow rapidly in the presence of higher concentrations of the metals indicating good metal resistance by the bacterium. Compared to normally grown cells, A. symbioticum KM2, when grown in presence of the metals, became more hydrophobic, which was dependent on the metal and its concentration in the media. Among the four metals studied, the effect of copper was found to be the highest, where up to 74 % increase in the bacterial cell hydrophobicity was observed.



Geochemistry ◽  
2005 ◽  
Vol 65 ◽  
pp. 131-144 ◽  
Author(s):  
Andre Schmidt ◽  
Götz Haferburg ◽  
Manuel Sineriz ◽  
Dirk Merten ◽  
Georg Büchel ◽  
...  


2016 ◽  
Vol 75 (s2) ◽  
Author(s):  
Andrea Di Cesare ◽  
Ester Eckert ◽  
Gianluca Corno

<p class="p1">Antibiotic resistant bacteria are found in most environments, especially in highly anthropized waters. A direct correlation between human activities (<em><span class="s1">e.g., </span></em>pollution) and spread and persistence of antibiotic resistant bacteria (ARB) and resistance genes (ARGs) within the resident bacterial communities appears more and more obvious. Furthermore, the threat posed for human health by the presence of ARB and ARGs in these environments is enhanced by the risk of horizontal gene transfer of resistance genes to human pathogens. Although the knowledge on the spread of antibiotic resistances in waters is increasing, the understanding of the driving factors determining the selection for antibiotic resistance in the environment is still scarce. Antibiotic pollution is generally coupled with contamination by heavy metals (HMs) and other chemicals, which can also promote the development of resistance mechanisms, often through co-selecting for multiple resistances. The co-selection of heavy metal resistance genes and ARGs in waters, sediments, and soils, increases the complexity of the ecological role of ARGs, and reduces the effectiveness of control actions. In this mini-review we present the state-of-the-art of the research on antibiotic- and HM-resistance and their connection in the environment, with a focus on HM pollution and aquatic environments. We review the spread and the persistence of HMs and/or ARB, and how it influences their respective gene co-selection. In the last chapter, we propose Lake Orta, a system characterized by an intensive HM pollution followed by a successful restoration of the chemistry of the water column, as a study-site to evaluate the spread and selection of HMs and antibiotic resistances in heavily disturbed environments.</p>



2009 ◽  
Vol 71-73 ◽  
pp. 279-282 ◽  
Author(s):  
A. Orell ◽  
C.A. Navarro ◽  
Carlos A. Jerez

Extremophiles such as the acidophilic Sulfolobus metallicus (Archaea) and Acidithiobacillus ferrooxidans (Bacteria) can resist Cu (CuSO4) concentrations of 200 mM and 800 mM respectively. These microorganisms are important in biomining processes to extract copper and other metals. A. ferrooxidans grown at low Cu concentrations (5 mM) expressed genes coding for ATPases most likely involved in pumping the metal from the cytoplasm to the periplasm of the bacterium. At 100 mM Cu the previous systems were repressed and there was a great induction in the expression of efflux systems known to use the proton motive force energy to export the metal outside the cell. These Cu-resistance determinants from A. ferrooxidans were found to be functional since when expressed in Escherichia coli they conferred higher Cu tolerance to it. Novel Cu-resistance determinants for A. ferrooxidans were found and characterized. S. metallicus possessed at least 2 CopM metallochaperones and 2 CopA ATPases whose expressions were induced by Cu (5 to 50 mM). Furthermore, we previously reported that both microorganisms accumulate high levels of inorganic polyphosphate (PolyP) and that intracellular Cu concentration stimulates polyP hydrolysis. The resulting Pi would then be transported out of the cell as a metal-Pi complex to detoxify the cells. In addition, our results suggest that at high Cu concentrations polyP could also provide energy for the metal efflux. All the data suggest that both biomining microorganisms use different systems to respond to Cu depending on the extracellular concentrations of the metal and suggest that the presence of different additional systems to respond to Cu may explain the extremely high metal resistance of these extremophiles.



Plasmid ◽  
1992 ◽  
Vol 27 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Simon Silver




2021 ◽  
Vol 75 (2) ◽  
pp. 103-115
Author(s):  
Ana Volaric ◽  
Zorica Svircev ◽  
Dragana Tamindzija ◽  
Dragan Radnovic

Heavy metal pollution is one of the most serious environmental problems, due to metal ions persistence, bioavailability, and toxicity. There are many conventional physical and chemical techniques traditionally used for environmental clean-up. Due to several drawbacks regarding these methods, the use of living organisms, or bioremediation, is becoming more prevalent. Biotechnological application of microorganisms is already successfully implemented and is in constant development, with many microbial strains successfully removing heavy metals. This paper provides an overview of the main heavy metal characteristics and describes the interactions with microorganisms. Key heavy metal resistance mechanisms in microorganisms are described, as well as the main principles and types of heavy metal bioremediation methods, with details on successful pilot scale bioreactor studies. Special attention should be given to indigenous bacteria isolated from the polluted environments since such species are already adapted to contamination and possess resistance mechanisms. Utilization of bacterial biofilms or consortia could be advantageous due to higher resistance and a combination of several metabolic pathways, and thus, the possibility to remove several heavy metals simultaneously. Novel technologies covered in this review, such as nanotechnology, genetic engineering, and metagenomics, are being introduced to the field of bioremediation in order to improve the process. To conclude, bioremediation is a potentially powerful solution for cleaning the environment.



2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Anna E. Panyushkina ◽  
Vladislav V. Babenko ◽  
Anastasia S. Nikitina ◽  
Oksana V. Selezneva ◽  
Iraida A. Tsaplina ◽  
...  

Abstract The first complete genome of the biotechnologically important species Sulfobacillus thermotolerans has been sequenced. Its 3 317 203-bp chromosome contains an 83 269-bp plasmid-like region, which carries heavy metal resistance determinants and the rusticyanin gene. Plasmid-mediated metal resistance is unusual for acidophilic chemolithotrophs. Moreover, most of their plasmids are cryptic and do not contribute to the phenotype of the host cells. A polyphosphate-based mechanism of metal resistance, which has been previously unknown in the genus Sulfobacillus or other Gram-positive chemolithotrophs, potentially operates in two Sulfobacillus species. The methylcitrate cycle typical for pathogens and identified in the genus Sulfobacillus for the first time can fulfill the energy and/or protective function in S. thermotolerans Kr1 and two other Sulfobacillus species, which have incomplete glyoxylate cycles. It is notable that the TCA cycle, disrupted in all Sulfobacillus isolates under optimal growth conditions, proved to be complete in the cells enduring temperature stress. An efficient antioxidant defense system gives S. thermotolerans another competitive advantage in the microbial communities inhabiting acidic metal-rich environments. The genomic comparisons revealed 80 unique genes in the strain Kr1, including those involved in lactose/galactose catabolism. The results provide new insights into metabolism and resistance mechanisms in the Sulfobacillus genus and other acidophiles.



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