The Role of Glycerol in the Osmotic Regulation of the Halophilic Alga Dunaliella parva.

@article{BenAmotz1973TheRO,
  title={The Role of Glycerol in the Osmotic Regulation of the Halophilic Alga Dunaliella parva.},
  author={Ami Ben‐Amotz and Mordhay Avron},
  journal={Plant physiology},
  year={1973},
  volume={51 5},
  pages={
          875-8
        }
}
Dunaliella parva, a green halophilic alga, was found to accumulate very large amounts of intracellular glycerol. Through measurements of the intracellular volume the internal concentration of glycerol was calculated and found to be around 2.1 m in cells cultured in 1.5 m NaCl. When the extracellular salt concentration of an algal suspension was increased or decreased, the intracellular glycerol varied accordingly, reaching its new osmotic equilibrium after about 90 minutes. Since no leakage of… 

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ADAPTATION OF THE UNICELLULAR ALGA DUNALIELLA PARVA TO A SALINE ENVIRONMENT 1

Determination of the glycerol sensitivity of enzymic and photosynthetic reactions of cell‐free preparations from D. parva showed a broad range of tolerance to high concentrations of Glycerol, interpreted as due to metabolic formation and degradation of intracellularglycerol.

The role of intracellular orthophosphate in triggering osmoregulation in the alga Dunaliella salina.

The Pi-dependent response was investigated in vivo using NMR and the rates of glycerol synthesis or elimination following osmotic shocks were modulated by the intracellular Pi level as predicted by the hypothesis.

Effect of temperature on glycerol retention in the halotolerant algae dunaliella and asteromonas.

Algae of the genera Dunaliella and Asteromonas can maintain extremely high concentration gradients between the intracellular space and the medium, which is highly temperature-dependent and independent of the salt concentration of the medium.

Glycerol production by Dunaliella

Growth studies of Dunaliella indoors and outdoors showed that salt concentrations favoring maximal glycerol productivity are not identical with those required for maximal algal productivity, and 3 new enzymes, NADPH-dihydroxyacetone-reductase, dihydroxyacet one kinase and glycerl-1-phosphatase seem to be involved in the osmoregulatory response via glycerols in DunalIElla and Asteromonas.

Release of intracellular glycerol and pore formation in Dunaliella tertiolecta exposed to hypotonic stress

Results indicate that intracellular glycerol is rapidly released without significant concomitant cell damage and that rubidum, in the case of rubidium-loaded cells, was also rapidly released to the medium in response to hypotonic shock.

Osmoregulation in the Halotolerant Alga Asteromonas gracilis.

The above results indicate the existence of osmotic regulations in Asteromonas gracilis via the accumulation of intracellular glycerol and the kinetics of photosynthetic resumption preceded the Kinetics of glycerl biosynthesis.

The salt relations of marine and halophilic species of the unicellular green alga,Dunaliella

It is concluded that the different salt tolerances of the two algae cannot be explained by generalized differences between their enzyme proteins, and its primary function in influencing their salt relations is considered to be that of a compatible solute.
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