Consulta: subjectFacets:"Cellular states"
Registros recuperados: 2
Data/hora: 01/06/2024 08:38:36

Responses of enteric bacteria to environmental stresses in seawater
Provedor de dados: 5
Autores: Troussellier, Marc; Bonnefont, Jean-luc; Courties, Claude; Derrien, Annick; Dupray, Elizabeth; Gauthier, Michel; Gourmelon, Michele; Joux, Fabien; Lebaron, Philippe; Martin, Yvan; Pommepuy, Monique.
The effects of different environmental factors (nutrient deprivation, hyperosmotic shock, exposure to light) on enteric bacteria which have been transferred into the marine environment, have been studied experimentally (microcosms) by considering demographic, physiological and genetic responses in Escherichia coli or Salmonella typhimurium populations. Short-term experiments (less than or equal to 48 h) showed that nutrient deprivation induced limited changes in measured bacteriological variables, but when combined with hyperosmotic shock, it results in an energy charge decrease and inactivation of membrane transport. Light exposure mainly affects the colony-forming capacity of bacterial populations. Combining different stress factors confirmed the rapid...
Tipo: Text
Palavras-chave: Genetics; Cellular states; Physiology; Seawater; Enteric bacteria; Génétique; Etats cellulaires; Physiologie; Eau de mer; Entérobactéries.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-845.pdf

Adaptative responses of E-coli to marine environmental stresses. a modelling approach based on viability and dormancy concepts
Provedor de dados: 5
Autores: Martin, Y; Troussellier, Marc; Bonnefont, Jl.
In an attempt to synthesize conceptual and experimental information on the behaviour of enteric bacteria in seawater, a mathematical model has been developed. This model is based on changes in intracellular metabolisable components depending an physiological responses of the cell when subjected to nutrient starvation, salinity stress and solar radiation. Following a strategy which takes into account short- and mid-term physiological adaptation and reversal processes, the cells can develop in different states: culturable (B-1), viable and definitively nonculturable (B-2), and reversibly dormant (B-3) cells. Model parameters were deduced either from original microcosm experiments, from literature data or calibration procedures. Validation of the model was...
Tipo: Text
Palavras-chave: Escherichia coli; Eau de mer; Stress; États cellulaires; Modélisation; Escherichia coli; Seawater; Stress; Cellular states; Modelling.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00325/43646/43224.pdf