Compatible solutes in new moderately halophilic isolates

Moral, Ana; Severin, Jörg; Ramos‐Cormenzana, A.; Trüper, Hans G.; Galinski, Erwin A.

doi:10.1111/j.1574-6968.1994.tb07160.x

Cited by 25 publications

(12 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All spectra were obtained with a Bruker model AMX500 spectrometer. 13 C NMR spectra were obtained at 125.77 MHz by using a 5-mm carbon selective probe head. Typically, spectra were acquired with a repetition delay of 1.5 s and a pulse width of 7 s corresponding to a 90°flip angle.…”

Section: Methodsmentioning

confidence: 99%

Effects of Temperature, Salinity, and Medium Composition on Compatible Solute Accumulation by Thermococcus spp

Lamosa

Martins

Costa

et al. 1998

Appl Environ Microbiol

102

View full text Add to dashboard Cite

The effects of salinity and growth temperature on the accumulation of intracellular organic solutes were examined by nuclear magnetic resonance spectroscopy (NMR) in Thermococcus litoralis,Thermococcus celer, Thermococcus stetteri, andThermococcus zilligii (strain AN1). In addition, the effects of growth stage and composition of the medium were studied inT. litoralis. A novel compound identified as β-galactopyranosyl-5-hydroxylysine was detected in T. litoralis grown on peptone-containing medium. Besides this newly discovered compound, T. litoralis accumulated mannosylglycerate, aspartate, α-glutamate, di-myo-inositol-1,1′(3,3′)-phosphate, hydroxyproline, and trehalose. The hydroxyproline and β-galactopyranosyl-5-hydroxylysine were probably derived from peptone, while the trehalose was derived from yeast extract; none of these three compounds was detected in the other Thermococcus strains examined. Di-myo-inositol-1,1′(3,3′)-phosphate, aspartate, and mannosylglycerate were detected in T. celer and T. stetteri, and the latter organism also accumulated α-glutamate. The only nonmarine species studied, T. zilligii, accumulated very low levels of α-glutamate and aspartate. The levels of mannosylglycerate and aspartate increased in T. litoralis, T. celer, and T. stetteri in response to salt stress, while di-myo-inositol-1,1′(3,3′)-phosphate was the major intracellular solute at supraoptimal growth temperatures. The phase of growth had a strong influence on the types and levels of compatible solutes in T. litoralis; mannosylglycerate and aspartate were the major solutes during exponential growth, while di-myo-inositol-1,1′(3,3′)-phosphate was the predominant organic solute during the stationary phase of growth. This work revealed an unexpected ability of T. litoralis to scavenge suitable components from the medium and to use them as compatible solutes.

show abstract

Section: Methodsmentioning

confidence: 99%

Effects of Temperature, Salinity, and Medium Composition on Compatible Solute Accumulation by Thermococcus spp

Lamosa

Martins

Costa

et al. 1998

Appl Environ Microbiol

102

View full text Add to dashboard Cite

show abstract

“…Organisms that thrive in high salinity environments possess speci¢c mechanisms to adjust their internal osmotic status. One such mechanism that helps organisms to become more tolerant to salt stress is the accumulation of low molecular mass osmolytes such as ectoine [3], glycine betaine [4], proline [5], and polyamines [6].…”

Section: Introductionmentioning

confidence: 99%

Content and biosynthesis of polyamines in salt and osmotically stressed cells ofSynechocystissp. PCC 6803

Jantaro

Mäenpää

Mulo

et al. 2003

FEMS Microbiology Letters

View full text Add to dashboard Cite

The effects of various NaCl and sorbitol concentrations in the growth medium on polyamine content and on two enzymes of the polyamine biosynthesis pathway, arginine decarboxylase (ADC) and S-adenosyl methionine decarboxylase (SAMDC), were investigated in the unicellular cyanobacterium Synechocystis sp. PCC 6803. Synechocystis cells showed no difference in growth rate when the concentration of NaCl was raised up to 550 mM. The growth rate decreased at 300 mM sorbitol, and complete inhibition of growth occurred at concentrations of v 700 mM sorbitol. Salt stress induced a moderate increase in the total cellular polyamine content, spermine in particular. Osmotic stress caused an apparent increase in the total cellular polyamine content with a marked increase of spermidine induced by 700 mM sorbitol. Importantly, a low level of spermine, which so far has never been detected in cyanobacteria, could be found in Synechocystis sp. PCC 6803. ADC, a key enzyme for putrescine synthesis, was unaffected by salt stress but showed a six-fold increase in enzyme activity upon osmotic stress imposed by 700 mM sorbitol. SAMDC, another important enzyme for spermidine and spermine synthesis, responded to salt and osmotic stresses similarly to the pattern observed for ADC. An analysis by reverse transcription-polymerase chain reaction revealed an increase of ADC mRNA level in cells under salt and osmotic stresses. Most importantly, the increase of ADC mRNA was attributed to its slower turnover rate under both stress conditions. Interestingly, the samdc gene(s) of Synechocystis appear to be unique since comparisons with known gene sequences from other organisms resulted in no homologous sequences identified in the Synechocystis genome. ß

show abstract

“…Therefore, every microbe living in such an environment has to cope with changing salinities over a very wide range, from about 0 to 3.5 M NaCl. It has often been reported that microorganisms use not just one solute but rather two or more to meet this challenge (6,23,33,36), but little is known about the salinity-dependent regulation of intracellular solute composition. Since it has been reported many times in the literature that compatible solutes in general have common features but nevertheless exhibit very distinct properties in protecting proteins under different stress conditions (for a review, see reference 8), it is very likely that an organism has to switch from solute A, which is optimal at low salinities, to solute B, which serves better at high salinities, after osmotic upshock.…”

mentioning

confidence: 99%

Salinity-Dependent Switching of Osmolyte Strategies in a Moderately Halophilic Bacterium: Glutamate Induces Proline Biosynthesis in Halobacillus halophilus

2007

View full text Add to dashboard Cite

. 188:6808-6815, 2006). Here, we report that H. halophilus switches its osmolyte strategy and produces proline as the dominant solute at higher salinities (2 to 3 M NaCl). The proline biosynthesis genes proH, proJ, and proA were identified. They form a transcriptional unit and encode the pyrroline-5-carboxylate reductase, the glutamate-5-kinase, and the glutamate-5-semialdehyde dehydrogenase, respectively, catalyzing proline biosynthesis from glutamate. Expression of the genes was clearly salinity dependent and reached a maximum at 2.5 M NaCl, indicating that the pro operon is involved in salinity-induced proline biosynthesis. To address the role of anions in the process of pro gene activation and proline biosynthesis, we used a cell suspension system. Chloride salts lead to the highest accumulation of proline. Interestingly, chloride could be substituted to a large extent by glutamate salts. This unexpected finding was further analyzed on the transcriptional level. The cellular mRNA levels of all three pro genes were increased up to 90-fold in the presence of glutamate. A titration revealed that a minimal concentration of 0.2 M glutamate already stimulated pro gene expression. These data demonstrate that the solute glutamate is involved in the switch of osmolyte strategy from glutamate to proline as the dominant compatible solute during the transition from moderate to high salinity.

show abstract

Compatible solutes in new moderately halophilic isolates

Cited by 25 publications

References 24 publications

Effects of Temperature, Salinity, and Medium Composition on Compatible Solute Accumulation by Thermococcus spp

Effects of Temperature, Salinity, and Medium Composition on Compatible Solute Accumulation by Thermococcus spp

Content and biosynthesis of polyamines in salt and osmotically stressed cells ofSynechocystissp. PCC 6803

Salinity-Dependent Switching of Osmolyte Strategies in a Moderately Halophilic Bacterium: Glutamate Induces Proline Biosynthesis in Halobacillus halophilus

Contact Info

Product

Resources

About