Intracellular salt concentrations of the anaerobic halophilic eubacteria Haloanaerobium praevalens and Halobacteroides halobius

1986 ◽  
Vol 32 (1) ◽  
pp. 4-9 ◽  
Author(s):  
Aharon Oren
Keyword(s):  
Amino Acids ◽  
Salt Lake ◽  
Compatible Solutes ◽  
Chloride Concentration ◽  
Dead Sea ◽  
Intracellular Potassium ◽  
Acidic Amino Acids ◽  
Nacl Concentration ◽  
Halophilic Archaebacteria ◽  
Eukaryotic Organisms

The obligately anaerobic, moderately halophilic eubacteria Haloanaerobium praevalens (isolated from Great Salt Lake, Utah) and Halobacteroides halobius (isolated from the Dead Sea) were found to contain high intracellular potassium concentrations (0.76–2.05 M, not well correlated with the external NaCl concentration), and high intracellular sodium concentrations (0.28–2.6 M, increasing with increasing extracellular NaCl concentration). The sum of intracellular potassium and sodium concentrations approximated the total cation concentration of the medium. Internal chloride concentrations in Haloanaerobium praevalens equalled the external chloride concentration. Organic solutes, such as betaine, glycerol, and different amino acids that have been shown to serve as compatible solutes in other halophilic eubacteria and eukaryotic organisms, were not found in significant concentrations. Analysis of the amino acids in the proteins of the anaerobic halophilic eubacteria showed an excess of acidic amino acids, similar to that reported in halophilic archaebacteria of the genus Halobacterium.

scholarly journals Comparative study of salinity effects on ionic balance and compatible solutes in nine Iranian table grape (Vitis vinifera L.) genotypes

OENO One ◽  
2013 ◽  
Vol 47 (2) ◽  
pp. 99
Author(s):  
Nayer Mohammadkhani ◽  
Reza Heidari ◽  
Nasser Abbaspour ◽  
Fatemeh Rahmani
Keyword(s):  
Vitis Vinifera ◽  
Salt Lake ◽  
Soluble Sugar ◽  
Compatible Solutes ◽  
Table Grape ◽  
The Other ◽  
Ionic Balance ◽  
High Positive Correlation ◽  
Nacl Concentration ◽  
Improvement Programs

<p style="text-align: justify;"><strong>Aim</strong>: To study the salinity tolerance of own rooted grape cuttings taken from nine table grape (<em>Vitis vinifera</em> L.) genotypes growing in the Urmia Salt Lake region (Iran): LaaleBidaneh, Gharashani, Sachagh, Shahroodi, LaaleSefid, Khalili, Chawga, GhezelUzum and Gharagandomeh.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Plants were treated with nutrient solutions containing 0, 25, 50 and 100 mM NaCl for two weeks. Shoot and root growth and dry weights (DW) were significantly (<em>P</em>&lt;0.05) reduced in all treatments. Chloride (Cl<sup>-</sup>) and sodium (Na<sup>+</sup>) ions highly accumulated in the various parts of the vines with increasing external NaCl concentration. Na<sup>+</sup> accumulation exceeded that of Cl<sup>-</sup> in all treatments and all genotypes. However, Gharashani showed a higher ability to restrict Cl<sup>-</sup> and Na<sup>+</sup> accumulation in lamina (1.08% of DW and 2.56% of DW, respectively) in comparison to the other genotypes, particularly to GhezelUzum (4.1% of DW and 9.10% of DW, respectively), which showed intensive leaf burn symptoms. Lamina soluble sugar, proline and glycine betaine contents increased with increasing salinity. Correlation analysis (<em>P</em>&lt;0.01) indicated that there was a high positive correlation between Cl<sup>-</sup> and Na<sup>+</sup> contents and osmolyte accumulation in lamina.</p><p style="text-align: justify;"><strong>Conclusion</strong>: Taken together, it seems that Gharashani and GhezelUzum, respectively, had a higher and a lower capacity to alleviate salt stress symptoms when compared to the other genotypes.</p><p style="text-align: justify;"><strong>Significance and impact of the study</strong>: Salinity is a serious environmental stress in the regions around Urmia Salt Lake and grapevine is one of the most economically important fruit crops in Urmia. Therefore, screening the native grape genotypes for salt tolerance and using the tolerant genotypes directly as rootstocks or producing hybrids with desirable traits could be one of the improvement programs for viticulture in this area.</p>

scholarly journals Characterization of Virus Adsorption by Using DEAE-Sepharose and Octyl-Sepharose

2002 ◽  
Vol 68 (8) ◽  
pp. 3965-3968 ◽  
Author(s):  
Patricia A. Shields ◽  
Samuel R. Farrah
Keyword(s):  
Sodium Chloride ◽  
Electrostatic Interactions ◽  
Hydrophobic Interactions ◽  
Chloride Concentration ◽  
Sodium Chloride Concentration ◽  
Virus Adsorption ◽  
Nacl Concentration

ABSTRACT Viruses were characterized by their adsorption to DEAE-Sepharose or by their elution from octyl-Sepharose by using buffered solutions of sodium chloride with different ionic strengths. Viruses whose adsorption to DEAE-Sepharose was reduced most rapidly by an increase in the sodium chloride concentration were considered to have the weakest electrostatic interactions with the solids; these viruses included MS2, E1, and φX174. Viruses whose adsorption to DEAE-Sepharose was reduced least rapidly were considered to have the strongest electrostatic interactions with the column; these viruses included P1, T4, T2, and E5. All of the viruses studied adsorbed to octyl-Sepharose in the presence of 4 M NaCl. Viruses that were eluted most rapidly following a decrease in the concentration of NaCl were considered to have the weakest hydrophobic interactions with the column; these viruses included φX174, CB4, and E1. Viruses that were eluted least rapidly from the columns after the NaCl concentration was decreased were considered to have the strongest hydrophobic interactions with the column; these viruses included f2, MS2, and E5.

The entry of acidic amino acids into brain and CSF during development, using in situ perfusion in the rat

1995 ◽  
Vol 90 (1-2) ◽  
pp. 151-158 ◽  
Author(s):  
Hameed Al-Sarraf ◽  
Jane E. Preston ◽  
Malcolm B. Segal
Keyword(s):  
Amino Acids ◽  
In Situ Perfusion ◽  
Acidic Amino Acids

scholarly journals Effects of Fe+2 and Fe+3 in Pretreatment and Leaching on a Mixed Copper Ore in Chloride Media

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 866
Author(s):  
María E. Taboada ◽  
Pía C. Hernández ◽  
Aldo P. Padilla ◽  
Nathalie E. Jamett ◽  
Teófilo A. Graber
Keyword(s):  
Chloride Concentration ◽  
Solution Concentration ◽  
Copper Extraction ◽  
Curing Time ◽  
Ferrous Ions ◽  
Copper Ore ◽  
Second Stage ◽  
Acid Consumption ◽  
Nacl Concentration ◽  
Leaching Solution

A study of the pretreatment stage and subsequent leaching of a mixed copper ore with different chloride solutions containing iron was carried out. The first stage considered pretreatment tests to decide the best conditions. Two levels of each factor were analyzed, 20 and 50 kg/t of NaCl, 17 and 25 kg/t of H2SO4, 0 and 25 kg/t of Fe2(SO4)3·9.2H2O, 0 and 25 kg/t of Fe2SO4·7H2O, and a curing time of 15 and 30 days. The results showed a significant effect of NaCl and curing time on the extraction, and less effect was found with the variation of acid and iron salts. The second stage included column leaching using a solution with 0.5 g/L of Cu+2, 80 g/L of Cl−, 10 g/L of H2SO4, and variable concentrations of ferric and ferrous ions (0 and 2 g/L). The best copper extraction of 80.2% was found considering a pretreatment of 30 days, 25 kg/t of H2SO4, 50 kg/t of NaCl, and a leaching solution concentration described previously with 2 g/L of Fe+2. The results showed the leaching of all copper oxide species and 20% of the copper sulfide species. In addition, there was a reduction in the acid consumption as the resting time increases. Furthermore, to evaluate a possible decrease in time and acid in pretreatment and chloride in leaching, tests including 10 and 25 kg/t of H2SO4 and 1, 15, and 30 days of curing and a diminution of the NaCl concentration to 20 g/L (content from seawater) were executed. The results showed a significant effect on curing time below 15 days. Furthermore, the slight influence of the decrease of acid on copper extraction gives cost reduction opportunities. The diminution of chloride concentration (80 to 20 g/L) in leaching solution decreases the extraction from 79% to 66.5%. Finally, the Mellado leaching kinetic model was successfully implemented.

scholarly journals Extensive mutagenesis of a transcriptional activation domain identifies single hydrophobic and acidic amino acids important for activation in vivo.

1997 ◽  
Vol 17 (1) ◽  
pp. 115-122 ◽  
Author(s):  
M B Sainz ◽  
S A Goff ◽  
V L Chandler
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Transcriptional Activation ◽  
Carboxyl Terminus ◽  
Wild Type ◽  
Activation Domain ◽  
Hydrophobic Residues ◽  
Transcriptional Activation Domain ◽  
Acidic Amino Acids

C1 is a transcriptional activator of genes encoding biosynthetic enzymes of the maize anthocyanin pigment pathway. C1 has an amino terminus homologous to Myb DNA-binding domains and an acidic carboxyl terminus that is a transcriptional activation domain in maize and yeast cells. To identify amino acids critical for transcriptional activation, an extensive random mutagenesis of the C1 carboxyl terminus was done. The C1 activation domain is remarkably tolerant of amino acid substitutions, as changes at 34 residues had little or no effect on transcriptional activity. These changes include introduction of helix-incompatible amino acids throughout the C1 activation domain and alteration of most single acidic amino acids, suggesting that a previously postulated amphipathic alpha-helix is not required for activation. Substitutions at two positions revealed amino acids important for transcriptional activation. Replacement of leucine 253 with a proline or glutamine resulted in approximately 10% of wild-type transcriptional activation. Leucine 253 is in a region of C1 in which several hydrophobic residues align with residues important for transcriptional activation by the herpes simplex virus VP16 protein. However, changes at all other hydrophobic residues in C1 indicate that none are critical for C1 transcriptional activation. The other important amino acid in C1 is aspartate 262, as a change to valine resulted in only 24% of wild-type transcriptional activation. Comparison of our C1 results with those from VP16 reveal substantial differences in which amino acids are required for transcriptional activation in vivo by these two acidic activation domains.

Major Compatible Solutes and Structural Adaptation of Proteins in Extremophiles

2022 ◽  
pp. 161-186
Author(s):  
Hardik Shah ◽  
Khushbu Panchal ◽  
Amisha Panchal
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Osmotic Stress ◽  
Amino Acid Composition ◽  
Scientific Community ◽  
Compatible Solutes ◽  
Organic Solutes ◽  
Structural Adaptation ◽  
Extreme Habitats

Extremophiles are the most ancient microbes on the Earth and also a center of attraction for the scientific community for research because of their ability to adapt to extreme habitats. Compatible solutes are among those factors which enable these microorganisms to thrive in such extreme habitats. Under osmotic stress, the majority of extremophiles accumulate specific organic solutes such as amino acids, sugars, polyols, and their derivatives. In addition, proteins in extremophiles are found to be evolved by changing their amino acid composition to alter the hydrophobicity of its core and surface charge to maintain activity. This chapter encompasses a comprehensive study about the role of various compatible solutes in the endurance of microorganisms under extremophilic conditions, synthesis of compatible solutes, nature of extremophilic proteins, and their applications. Furthermore, an attempt has been made to cover various strategies adopted by the scientific community while pursuing research on compatible solutes.

scholarly journals The Effects of Possible Contamination on the Radiocarbon Dating of the Dead Sea Scrolls II: Empirical Methods to Remove Castor Oil and Suggestions for Redating

Radiocarbon ◽  
2009 ◽  
Vol 51 (3) ◽  
pp. 1005-1022 ◽  
Author(s):  
Kaare Lund Rasmussen ◽  
Johannes van der Plicht ◽  
Gregory Doudna ◽  
Frederik Nielsen ◽  
Peter Højrup ◽  
...  
Keyword(s):  
Amino Acids ◽  
Castor Oil ◽  
Radiocarbon Dating ◽  
Soxhlet Extraction ◽  
Dead Sea Scrolls ◽  
Dead Sea ◽  
Empirical Methods ◽  
Advantages And Disadvantages ◽  
The Dead ◽  
East Jerusalem

While kept at the Rockefeller Museum in East Jerusalem, many Dead Sea Scroll fragments were exposed to castor oil by the original team of editors in the course of cleaning the parchments. Castor oil must be regarded as a serious contaminant in relation to radiocarbon dating. If modern castor oil is present and is not removed prior to dating, the 14C dates will be skewed artificially towards modern values. In Rasmussen et al. (2001), it was shown that the standard AAA pretreatment procedure used in the 2 previous studies dating Dead Sea Scroll samples (Bonani et al. 1992; Jull et al. 1995) is not capable of removing castor oil from parchment samples. In the present work, we show that it is unlikely that castor oil reacts with the amino acids of the parchment proteins, a finding which leaves open the possibility of devising a cleaning method that can effectively remove castor oil. We then present 3 different pretreatment protocols designed to effectively remove castor oil from parchment samples. These involve 3 different cleaning techniques: extraction with supercritical CO2, ultrasound cleaning, and Soxhlet extraction—each with their own advantages and disadvantages. Our data show that the protocol involving Soxhlet extraction is the best suited for the purpose of decontaminating the Dead Sea Scrolls, and we recommend that this protocol be used in further attempts to 14C date the Dead Sea Scrolls. If such an attempt is decided on by the proper authorities, we propose a list of Scroll texts, which we suggest be redated in order to validate the 14C dates done earlier by Bonani et al. (1992) and Jull et al. (1995).

Amino acid transport by juxtamedullary nephrons: distal reabsorption and recycling

1988 ◽  
Vol 255 (3) ◽  
pp. F397-F407 ◽  
Author(s):  
W. H. Dantzler ◽  
S. Silbernagl
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Amino Acid Transport ◽  
Acid Transport ◽  
Acidic Amino Acids ◽  
Vasa Recta ◽  
Collecting Ducts ◽  
Distal Site

Amino acid transport by juxtamedullary (JM) nephrons and its relationship to transport by superficial cortical (SC) nephrons and to function of vasa recta and collecting ducts were examined in vivo and in situ by free-flow micropuncture of Henle's loops, collecting ducts, and vasa recta and by continuous microinfusion of Henle's loops in exposed rat papillae. Fractional deliveries (FDs) of six neutral amino acids, two acidic amino acids, and taurine to tips of Henle's loops of JM nephrons could be substantially below those to early distal loops of SC nephrons, indicating that reabsorption before loop tips could be greater in JM than in SC nephrons. FDs to collecting ducts lower than to JM loop tips suggested reabsorption distal to loop tips. This was confirmed by continuous microinfusion of ascending limbs of Henle's loops. Distal site of reabsorption is unknown, but amino acids may move passively out of the thin ascending limb and be recycled into vasa recta and descending limb. Recycling of amino acids was supported by high FDs to tips of Henle's loops (sometimes greater than 1.0), higher concentrations in ascending than in descending vasa recta at same papilla level, and high mean concentrations in vasa recta.

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