Osmoregulation in Pseudomonas aeruginosa under hyperosmotic shock.
Pseudomonas aeruginosa PAO1 strain was found to be able to tolerate 700 mM NaCl. 0.5 mM of the osmoprotectant betaine restablished the growth of this strain in 1200 mM NaCl. Intracellular K+ and glutamate concentrations of P. aeruginosa PAO1 after an hyperosmotic shock (400 mM NaCl) showed a permanent increase. Adition of betaine (0.5 mM) to the medium with NaCl had an inhibitory effect on the intracellular accumulation of glutamate. The results indicate that P. aeruginosa PAO1 resists high NaCl concentrations, K+ accumulation and glutamate synthesis probably being the first mechanisms involved in adaptation to osmotic stress. Also is is demonstrated that betaine modulates intracellular glutamate levels in osmotically stressed P. aeruginosa PAO1.
Velasco
R
R
Laboratorio de Osmorregulación, Universidad Nacional Autónoma de México.
Burgoa
R
R
Flores
E
E
Hernández
E
E
Villa
A
A
Vaca
S
S
D001622:Betaine / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D018698:Glutamic Acid / Q000378:metabolism; D007424:Intracellular Fluid / Q000378:metabolism; D009997:Osmotic Pressure; D011188:Potassium / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000502:physiology*; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*; D014882:Water-Electrolyte Balance
D012462:Saline Solution, Hypertonic; D018698:Glutamic Acid; D001622:Betaine; D011188:Potassium