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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
|
| pubmed:dateCreated |
1997-8-21
|
| pubmed:abstractText |
Mercury chloride toxicity was investigated in two strains of Chlorella and in a strain of Scenedesmus isolated from polluted areas in Tuscany (Italy). No Hg resistance was found in the autotrophic microorganisms isolated, but Scenedesmus sp. strain AR-2489, isolated from the Arno river, was able to grow at concentrations of up to 5 micrograms ml-1 of Hg. This concentration was twice that which inhibited growth of the two Chlorella strains and Scenedesmus acutus 8M, the reference strain from a culture collection. Photosynthesizing cells of Scenedesmus sp. AR-2489 showed reduced Hg uptake, with the highest percentage of Hg removal from the medium. Loss of Hg was not due to Hg(0) volatilization, as shown by a comparison test with the broad-spectrum Hg-resistant Pseudomonas putida FB1. The metabolic differences between Scenedesmus sp. strain AR-2489 and Siacatus strain 8M were: (1) higher growth rate (doubling time of 6.0 h versus 10.6 h); (2) higher O2 production rate (maximum 2 mumol h-1 mg-1 dry weight); and (3) higher intracellular pH during growth. The latter was imaged with a green fluorescence molecular probe (BCEFC-AM) and observed by scanning confocal laser microscopy (SCLM). The distribution of red-autofluorescence chlorophyll-a showed that strain AR-2489 had a rougher and hence more extended specific chloroplast surface than strain 8M. Hg tolerance in strain AR-2489 was related to the rapid increase in dissolved O2 in the medium and in intracellular pH; this caused a loss of soluble mercury transformed to insoluble mercury hydroxide, which is thermodynamically more stable at alkaline pH in highly oxygenated systems.
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Chlorophyll,
http://linkedlifedata.com/resource/pubmed/chemical/Culture Media,
http://linkedlifedata.com/resource/pubmed/chemical/Disinfectants,
http://linkedlifedata.com/resource/pubmed/chemical/Fluorescent Dyes,
http://linkedlifedata.com/resource/pubmed/chemical/Mercuric Chloride,
http://linkedlifedata.com/resource/pubmed/chemical/Pigments, Biological,
http://linkedlifedata.com/resource/pubmed/chemical/Soil Pollutants,
http://linkedlifedata.com/resource/pubmed/chemical/Water Pollutants, Chemical,
http://linkedlifedata.com/resource/pubmed/chemical/chlorophyll a
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Apr
|
| pubmed:issn |
0966-0844
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
10
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
85-94
|
| pubmed:dateRevised |
2010-11-18
|
| pubmed:meshHeading |
pubmed-meshheading:9210291-Chlorella,
pubmed-meshheading:9210291-Chlorophyll,
pubmed-meshheading:9210291-Chlorophyta,
pubmed-meshheading:9210291-Chloroplasts,
pubmed-meshheading:9210291-Culture Media,
pubmed-meshheading:9210291-Disinfectants,
pubmed-meshheading:9210291-Fluorescent Dyes,
pubmed-meshheading:9210291-Fresh Water,
pubmed-meshheading:9210291-Hydrogen-Ion Concentration,
pubmed-meshheading:9210291-Italy,
pubmed-meshheading:9210291-Mercuric Chloride,
pubmed-meshheading:9210291-Microscopy, Confocal,
pubmed-meshheading:9210291-Oxygen Consumption,
pubmed-meshheading:9210291-Photosynthesis,
pubmed-meshheading:9210291-Pigments, Biological,
pubmed-meshheading:9210291-Pseudomonas,
pubmed-meshheading:9210291-Reference Standards,
pubmed-meshheading:9210291-Soil Pollutants,
pubmed-meshheading:9210291-Species Specificity,
pubmed-meshheading:9210291-Volatilization,
pubmed-meshheading:9210291-Water Pollutants, Chemical
|
| pubmed:year |
1997
|
| pubmed:articleTitle |
Tolerance to mercury chloride in Scenedesmus strains.
|
| pubmed:affiliation |
Centro di Studio dei Microrganismi Autotrofi, CNR, Firenze, Italy.
|
| pubmed:publicationType |
Journal Article,
Comparative Study
|