Defense against lethal treatments and de novo protein synthesis induced by NaCl in Enterococcus faecalis ATCC 19433.
Enterococcus faecalis was strongly resistant to high osmotic pressure in complex medium; however, when it was subjected to a moderate osmotic stress [6.5% (w/v) NaCl or 52% (w/v) sucrose] for 2 h, it showed cross-protection against ethanol (22%), detergents stresses [bile sales (0.3%) and SDS (0.017%)], hydrogen peroxide challenge (45 mM), and to a minor extent against lethal temperature (62 degrees C). In response to salt stress [6.5% (w/v) NaCl], E. faecalis induced a large number of stress proteins. In addition, NaCl strongly induced the synthesis of many proteins more than tenfold. Although the acquired thermotolerance was inhibited markedly by chloramphenicol, the other NaCl-induced cross-tolerances seemed not to be correlated with de novo protein synthesis. The relationship between the stress protein synthesis and the induction of different types of cross-protection is discussed.
Flahaut
S
S
Laboratoire de Microbiologie de l'Environnement, Université de Caen, France.
Benachour
A
A
Giard
J C
JC
Boutibonnes
P
P
Auffray
Y
Y
D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000096:biosynthesis*; D001647:Bile Acids and Salts / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D015180:Electrophoresis, Gel, Two-Dimensional; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D000431:Ethanol / Q000494:pharmacology; D006360:Heat-Shock Proteins / Q000096:biosynthesis*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D009997:Osmotic Pressure; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology*; D012967:Sodium Dodecyl Sulfate / Q000494:pharmacology; D013395:Sucrose / Q000494:pharmacology; D013696:Temperature
D001426:Bacterial Proteins; D001647:Bile Acids and Salts; D006360:Heat-Shock Proteins; D011500:Protein Synthesis Inhibitors; D012967:Sodium Dodecyl Sulfate; D000431:Ethanol; D012965:Sodium Chloride; D013395:Sucrose; D002701:Chloramphenicol; D006861:Hydrogen Peroxide