Energy from solar ponds: control of the green flagellate Dunaliella, using osmotic shock of dilution

1989 ◽  
Vol 23 (2) ◽  
pp. 227-231 ◽  
Author(s):  
Inka Dor ◽  
Benjamin Doron
Keyword(s):  
Osmotic Shock ◽  
Solar Ponds ◽  
Green Flagellate

Effect of salinity on photosynthesis and mannitol synthesis in the green flagellate Platymonas suecica

1976 ◽  
Vol 54 (15) ◽  
pp. 1735-1741 ◽  
Author(s):  
Johan A. Hellebust
Keyword(s):  
High Salinity ◽  
Photosynthetic Capacity ◽  
Osmotic Shock ◽  
Linear Increase ◽  
Salinity Range ◽  
Content Increase ◽  
Lower Growth ◽  
Soluble Cell ◽  
Green Flagellate ◽  
Mannitol Concentration

Platymonas suecica, a brackish-water green flagellate belonging to the Prasinophyceae, grows almost at the same rate over a salinity range of 20–200% normal seawater, and at lower growth rates at salinities as high as 300% or as low as 10% seawater. Both cell size and carbon content increase significantly at salinities above 200% seawater, and there is a linear increase in intracellular mannitol concentration with increasing salinites from 50 to 300% seawater. This relationship between salinity and mannitol content indicates that mannitol is probably involved in osmoregulation in this alga. Photosynthesis is relatively little affected when cells adapted to low salinities are transferred to high salinities, while high-salinity-adapted cells suffer a temporary loss of much of their photosynthetic capacity when transferred to low salinities. It appears that this temporary loss of photosynthetic capacity in response to osmotic shock is due to a non-specific release of soluble cell constituents, including mannitol and amino acids, followed by regain of normal permeability properties and readjustment of cellular composition to the new osmotic environment.

Properties of Isolated Mitochondria of Agaricus Bisporus: Their Relationship to Dormancy and the Germination of Spores

1973 ◽  
Vol 31 ◽  
pp. 458-459
Author(s):  
K. S. McCarty ◽  
R. F. Weave ◽  
L. Kemper ◽  
F. S. Vogel
Keyword(s):  
Mitochondrial Dna ◽  
Ethidium Bromide ◽  
Microscopic Examination ◽  
Agaricus Bisporus ◽  
Osmotic Shock ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Isolated Mitochondria ◽  
Dna Strands ◽  
Cytoplasmic Ribosomes

During the prodromal stages of sporulation in the Basidiomycete, Agaricus bisporus, mitochondria accumulate in the basidial cells, zygotes, in the gill tissues prior to entry of these mitochondria, together with two haploid nuclei and cytoplasmic ribosomes, into the exospores. The mitochondria contain prominent loci of DNA [Fig. 1]. A modified Kleinschmidt spread technique1 has been used to evaluate the DNA strands from purified whole mitochondria released by osmotic shock, mitochondrial DNA purified on CsCl gradients [density = 1.698 gms/cc], and DNA purified on ethidium bromide CsCl gradients. The DNA appeared as linear strands up to 25 u in length and circular forms 2.2-5.2 u in circumference. In specimens prepared by osmotic shock, many strands of DNA are apparently attached to membrane fragments [Fig. 2]. When mitochondria were ruptured in hypotonic sucrose and then fixed in glutaraldehyde, the ribosomes were released for electron microscopic examination.

Short-term volume and turgor regulation in yeast

2008 ◽  
Vol 45 ◽  
pp. 147-160 ◽  
Author(s):  
Jörg Schaber ◽  
Edda Klipp
Keyword(s):  
Dynamic Model ◽  
Volume Change ◽  
Volume Regulation ◽  
Time Course ◽  
Osmotic Shock ◽  
Intracellular Concentration ◽  
Short Term ◽  
Hydrodynamic Property ◽  
Turgor Regulation ◽  
Thermodynamic Framework

Volume is a highly regulated property of cells, because it critically affects intracellular concentration. In the present chapter, we focus on the short-term volume regulation in yeast as a consequence of a shift in extracellular osmotic conditions. We review a basic thermodynamic framework to model volume and solute flows. In addition, we try to select a model for turgor, which is an important hydrodynamic property, especially in walled cells. Finally, we demonstrate the validity of the presented approach by fitting the dynamic model to a time course of volume change upon osmotic shock in yeast.

scholarly journals Visualization of Chromatin in the Yeast Nucleus and Nucleolus Using Hyperosmotic Shock

2021 ◽  
Vol 22 (3) ◽  
pp. 1132
Author(s):  
Nicolas Thelen ◽  
Jean Defourny ◽  
Denis L. J. Lafontaine ◽  
Marc Thiry
Keyword(s):  
Osmotic Shock ◽  
Size Composition ◽  
Yeast Cells ◽  
Exponential Growth Phase ◽  
Cell Nuclei ◽  
Hyperosmotic Shock ◽  
Christmas Trees ◽  
Transmission Electron ◽  
Active Transcription ◽  
Decondensed Chromatin

Unlike in most eukaryotic cells, the genetic information of budding yeast in the exponential growth phase is only present in the form of decondensed chromatin, a configuration that does not allow its visualization in cell nuclei conventionally prepared for transmission electron microscopy. In this work, we studied the distribution of chromatin and its relationships to the nucleolus using different cytochemical and immunocytological approaches applied to yeast cells subjected to hyperosmotic shock. Our results show that osmotic shock induces the formation of heterochromatin patches in the nucleoplasm and intranucleolar regions of the yeast nucleus. In the nucleolus, we further revealed the presence of osmotic shock-resistant DNA in the fibrillar cords which, in places, take on a pinnate appearance reminiscent of ribosomal genes in active transcription as observed after molecular spreading (“Christmas trees”). We also identified chromatin-associated granules whose size, composition and behaviour after osmotic shock are reminiscent of that of mammalian perichromatin granules. Altogether, these data reveal that it is possible to visualize heterochromatin in yeast and suggest that the yeast nucleus displays a less-effective compartmentalized organization than that of mammals.

scholarly journals Periplasmic synthesis and purification of the human prolactin antagonist Δ1-11-G129R-hPRL

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Miriam F. Suzuki ◽  
Larissa A. Almeida ◽  
Stephanie A. Pomin ◽  
Felipe D. Silva ◽  
Renan P. Freire ◽  
...  
Keyword(s):  
Size Exclusion Chromatography ◽  
High Performance ◽  
Signal Sequence ◽  
Osmotic Shock ◽  
Size Exclusion ◽  
Specific Expression ◽  
E Coli ◽  
Human Prolactin ◽  
Exclusion Chromatography

AbstractThe human prolactin antagonist Δ1-11-G129R-hPRL is a 21.9 kDa recombinant protein with 188 amino acids that downregulates the proliferation of a variety of cells expressing prolactin receptors. Periplasmic expression of recombinant proteins in E. coli has been considered an option for obtaining a soluble and correctly folded protein, as an alternative to cytoplasmic production. The aim of this work was, therefore, to synthesize for the first time, the Δ1-11-G129R-hPRL antagonist, testing different activation temperatures and purifying it by classical chromatographic techniques. E. coli BL21(DE3) strain was transformed with a plasmid based on the pET25b( +) vector, DsbA signal sequence and the antagonist cDNA sequence. Different doses of IPTG were added, activating under different temperatures, and extracting the periplasmic fluid via osmotic shock. The best conditions were achieved by activating at 35 °C for 5 h using 0.4 mM IPTG, which gave a specific expression of 0.157 ± 0.015 μg/mL/A600 at a final optical density of 3.43 ± 0.13 A600. Purification was carried out by nickel-affinity chromatography followed by size-exclusion chromatography, quantification being performed via high-performance size-exclusion chromatography (HPSEC). The prolactin antagonist was characterized by SDS-PAGE, Western blotting, reversed-phase high-performance liquid chromatography (RP-HPLC) and MALDI-TOF–MS. The final product presented > 95% purity and its antagonistic effects were evaluated in vitro in view of potential clinical applications, including inhibition of the proliferation of cancer cells overexpressing the prolactin receptor and specific antidiabetic properties, taking also advantage of the fact that this antagonist was obtained in a soluble and correctly folded form and without an initial methionine.

scholarly journals Metallo-enzymes Released from Escherichia coli by Osmotic Shock

1968 ◽  
Vol 243 (10) ◽  
pp. 2647-2653 ◽  
Author(s):  
H F Dvorak ◽  
L A Heppel
Keyword(s):  
Escherichia Coli ◽  
Osmotic Shock

A facile new modified method for the preparation of a new cerium-doped lanthanium cuperate perovskite energy storage system using nanotechnology

2021 ◽  
Author(s):  
Mervette El Batouti ◽  
H. A. Fetouh
Keyword(s):  
Solar Cells ◽  
Energy Storage ◽  
Dielectric Loss ◽  
Storage Systems ◽  
Low Cost ◽  
Storage System ◽  
Energy Storage System ◽  
Solar Ponds ◽  
Modified Method ◽  
Ferroelectric Perovskite

New ferroelectric perovskite sample: excellent dielectric, negligible dielectric loss for energy storage systems such as solar cells, solar ponds, and thermal collectors has been prepared at low cost using nanotechnology.

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