The ecology and taxonomy of anaerobic halophilic eubacteria

Oren, A

doi:10.1016/0378-1097(86)90056-x

Cited by 10 publications

(17 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Research on hypersaline ecosystems has led to the description of the family Haloanaerobiaceae (22,23), which now includes six genera and nine species (12, 21, 24, 25, 27, 35-37, 39, 40) (Table 3). The family consists of exclusively mesophilic Sporohalobacter marismortui ( ' Oligospores.…”

Section: Discussionmentioning

confidence: 99%

“…Indeed, the halophilic thermophilic bacteria studied so far are only slightly halophilic (haloduric) according to the scheme of Larsen (4,5,10,16) as the optimum NaCl requirement for growth is less than 5%. In the same domain, members of the family Haloanaerobiaceae are moderate halophiles (22,40) but are not able to grow up to or above 60°C (17). The halophiles found in the domain Archaea are extreme halophiles but are not true thermophiles.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Isolation and Characterization of Halothermothrix orenii gen. nov., sp. nov., a Halophilic, Thermophilic, Fermentative, Strictly Anaerobic Bacterium

Cayol¹,

Ollivier²,

Patel³

et al. 1994

International Journal of Systematic Bacteriology

113

View full text Add to dashboard Cite

The occurrence of thermophilic, halophilic anaerobic bacteria in the sediment of a Tunisian salted lake was tested in samples collected at 20-cm intervals down to a depth of 1.20 m. A long rod, present only in the 40-to 60-cm layer, was isolated at 60°C in a medium containing 100 g of NaCl per liter and designated strain H168. This strain produced acetate, ethanol, H,, and CO, from glucose metabolism. Fructose, xylose, ribose, cellobiose, and starch were also oxidized. The optimum temperature for growth was 60°C. No growth was obtained at 42 or 70°C. Strain H168 grew optimally in NaCl concentrations ranging from 50 to 100 g per liter, with the upper and lower limits of growth around 200 and 40 g per liter, respectively. The G+C ratio of the DNA was 39.6 mol%. Although halophilic, moderately thermophilic bacteria have been characterized among anaerobes, particularly within methanogens, strain H168 is the first true thermophilic (growing above 60°C) halophilic anaerobic bacterium described so far. The phylogeny, physiology, morphology, lipid content, and high G+C content of strain H168 are sufficiently different from those of genera belonging to the family Haloanaerobiaceae to justify the definition of a new genus.Extremophiles is a word coined to define microbes which live in extreme environments and includes thermophilic, halophilic, and alkalophilic members. All extremophiles are currently found among the domains Bacteria and Archaea (28,32). Intensive research has been conducted on extremophilic microbes, with particular emphasis being placed on thermophilic microbes as this group of organisms has great commercial potential for thermostable enzymes (9,14,33,34). Though a wide range of thermophilic physiological groups of bacteria is known to exist in the domain Bacteria, e.g., acidophiles, neutrophiles, aerobes, and anaerobes, very little is known about halophilic thermophiles. Indeed, the halophilic thermophilic bacteria studied so far are only slightly halophilic (haloduric) according to the scheme of Larsen (4, 5, 10, 16) as the optimum NaCl requirement for growth is less than 5%. In the same domain, members of the family Haloanaerobiaceae are moderate halophiles (22,40) but are not able to grow up to or above 60°C (17). The halophiles found in the domain Archaea are extreme halophiles but are not true thermophiles. Therefore, no true halophilic and thermophilic bacteria have been described so far.We report in this paper the first moderate halophilic thermophile (most rapid growth between 5 and 17.5% NaC1) which ferments carbohydrates to acetate, ethanol, H,, and CO,.(Part of this work was presented at the Annual Meeting of the American Society of Microbiology, Atlanta, Ga., 16 to 20 May 1993 [l]). MATERIALS AND METHODSOrigin of strain. The occurrence of thermophilic halophilic anaerobic bacteria in the sediment of a Tunisian hypersaline lake (Chott El Guettar) was tested in samples collected at The pH of the medium was adjusted to 7.0 with 10 M KOH, boiled under a stream of 0,-free N,, and cooled to room t...

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Isolation and Characterization of Halothermothrix orenii gen. nov., sp. nov., a Halophilic, Thermophilic, Fermentative, Strictly Anaerobic Bacterium

Cayol¹,

Ollivier²,

Patel³

et al. 1994

International Journal of Systematic Bacteriology

113

View full text Add to dashboard Cite

show abstract

“…Many works (Asker and Ohta, 1999;Joo and Kim, 2005;Mevarech et al, 2000;Oren, 1986;Trü per and Galinski, 1990) have been done on ecology, taxonomy, biosynthesis, production of compatible solutes (such as amino acids, sugars, and betaines), canthaxanthin, halophilic enzymes using halophilic bacteria, and proteomics of halophilic archaea.…”

Section: Introductionmentioning

confidence: 99%

Progress in decontamination by halophilic microorganisms in saline wastewater and soil

Zhuang

Han

Zhang

et al. 2010

Environmental Pollution

146

View full text Add to dashboard Cite

Review on the decontaminative capabilities of halophilic microorganisms in saline wastewater and soil. a r t i c l e i n f o a b s t r a c tEnvironments with high-salt concentrations are often populated by dense microbial communities. Halophilic microorganisms can be isolated from different saline environments and different strains even belonging to the same genus have various applications. Wastewater and soil rich in both organic matter and salt are difficult to treat using conventional microorganisms typically found in wastewater treatment and soil bioremediation facilities. Studies on decontaminative capabilities and decontamination pathways of organic contaminants (i.e., aromatic compounds benzoate, cinnamate, 3-phenylpropionate, 4-hydroxybenzoic acid), heavy metals (i.e., tellurium, vanadium), and nutrients in the biological treatment of saline wastewater and soil by halophilic microorganisms are discussed in this review.

show abstract

“…The composition of their cell envelopes differs from that of eubacterial cells, and they have high proportions of negatively charged proteins in their membranes, ribosomes, and other cell components. They are known to accumulate intracellular potassium ions to balance the extracellular sodium concentrations (16,25).The second group, the eubacterial halophiles, are far more widely distributed, both environmentally and among families and genera (19,22,32), and they are of great ecological and economic importance in agriculture, food industry, and other more specialized processes. The eubacterial halophiles also show more wide-ranging salt requirements and tolerances, i.e., they are more adaptable.…”

mentioning

confidence: 99%

“…The second group, the eubacterial halophiles, are far more widely distributed, both environmentally and among families and genera (19,22,32), and they are of great ecological and economic importance in agriculture, food industry, and other more specialized processes. The eubacterial halophiles also show more wide-ranging salt requirements and tolerances, i.e., they are more adaptable.…”

mentioning

confidence: 99%

Use of 23Na nuclear magnetic resonance spectroscopy to determine the true intracellular concentration of free sodium in a halophilic eubacterium

et al. 1991

View full text Add to dashboard Cite

We present new data obtained by 23Na nuclear magnetic resonance spectroscopy, which can distinguish free intracellular sodium from cell-bound sodium, showing that the intracellular concentration of Na+ the halophilic eubacterium Vibrio costicola is only 5 to 20% of that in the extracellular medium. Previous methods could not distinguish free intracellular Nn.' from that bound to cell structures, and it was believed that in halophilic eubacteria the total monovalent cation concentration inside matched that of the NaCl outside. Information obtained by the newer technology raises fundamental questions about the ways in which these organisms and others which live in hypersaline environments function and cope with osmotic stress.Halophilic bacteria belong to two major kingdoms. The archaebacterial extreme halophiles generally require 2 to 3 M NaCl and can grow in saturated brines (16,25). The composition of their cell envelopes differs from that of eubacterial cells, and they have high proportions of negatively charged proteins in their membranes, ribosomes, and other cell components. They are known to accumulate intracellular potassium ions to balance the extracellular sodium concentrations (16,25).The second group, the eubacterial halophiles, are far more widely distributed, both environmentally and among families and genera (19,22,32), and they are of great ecological and economic importance in agriculture, food industry, and other more specialized processes. The eubacterial halophiles also show more wide-ranging salt requirements and tolerances, i.e., they are more adaptable. The mechanisms and components which enable them to grow over such a wide range (from 3-to 10-fold, according to species) of salt concentrations are still largely unknown. One of the most important questions still unresolved involves the true intracellular ion concentrations relative to those in the medium and how the organisms deal with the osmotic and ionic gradients across their cell membranes. This problem has been highlighted by studies which showed that in vitro protein-synthesizing systems from such organisms (35) and most of their intracellular enzymes were inhibited by NaCl concentrations at which the cells had been grown (12,17,35). On the other hand, earlier studies of intracellular salt concentrations in such organisms suggested that the total concentration of intracellular cations was more or less equal to the cation concentration in the extracellular milieu (3,5,15,20,23,27,28,33

show abstract

The ecology and taxonomy of anaerobic halophilic eubacteria

Cited by 10 publications

References 16 publications

Isolation and Characterization of Halothermothrix orenii gen. nov., sp. nov., a Halophilic, Thermophilic, Fermentative, Strictly Anaerobic Bacterium

Isolation and Characterization of Halothermothrix orenii gen. nov., sp. nov., a Halophilic, Thermophilic, Fermentative, Strictly Anaerobic Bacterium

Progress in decontamination by halophilic microorganisms in saline wastewater and soil

Use of 23Na nuclear magnetic resonance spectroscopy to determine the true intracellular concentration of free sodium in a halophilic eubacterium

Contact Info

Product

Resources

About