Linked Life Data

9294237

Source:http://linkedlifedata.com/resource/pubmed/id/9294237

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1997-10-16
pubmed:abstractText
The thermophilic eubacterium Bacillus stearothermophilus has been used as a model system to identify DDT-promoted events in biological membranes putatively related with the insecticide toxicity. Two strategies have been approached: a) bacterial growth and viability were followed and the effects of DDT (2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane) determined; b) biophysical studies with fluorescent probes were performed to elucidate the effects of DDT on the organization of the membrane lipid bilayer. The effects of DDT on growth and physical properties of the membrane were also determined in the presence of Ca2+ to further identify the interference of the insecticide at the membrane level and its putative contribution to cell toxicity. Growth inhibition by DDT is concentration-dependent, being attenuated or removed by the addition of 2.5-mM Ca2+ to bacterial cultures. Consistently, fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) and its propionic acid derivative (DPH-PA) exhibited opposite effects of Ca2+ and DDT on the physical state of bacterial polar lipid dispersions. Growth and viability of bacterial cells are affected by DDT concentrations lower than those able to induce detectable bulk fluidity alterations, indicating high sensitivity of the intact bacterial system to alterations in limited membrane domains not directly probed by fluorescent probes that only report the average behavior of membrane lipid population.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0090-4341
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109-16
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Bacillus stearothermophilus as a model to evaluate membrane toxicity of a lipophilic environmental pollutant (DDT).
pubmed:affiliation
Centro de Neurociências, Departamento de Zoologia, Universidade de Coimbra, 3000 Coimbra, Portugal.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't